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BULLETIN 


OF THE 


* MUSEUM OF COMPARATIVE ZOOLOGY 


HARVARD COLLEGE, IN CAMBRIDGE. 


VOL. XXXII. 


CAMBRIDGE, MASS., U.S.A. 
1898 - 1899. 


QL 
\ 
H > 
Wy ge Re 


UNIVERSITY PRESS: 
Joun Wixtson AND Son, CamBripGe, U.S.A, 


613341 
+7 Sas 


CONTENTS. 


No. 1.— Studies from the Newport Marine Laboratory. XLI. On Dacry- 
LOMETRA. By A. Acassiz and A. G. Mayer. (13 Plates.) April, 1898 . 


No. 2,—On some Menus from Austratia. By A. AGassiz and A. G. 
Mayer. (3 Plates.) April, 1898 . 


No. 3.— The Gorpiacea of certain American Collections. With particular 
Reference to the North American Fauna. By T. H. Montcomery, Jr. 
(15 Plates.) April, 1898 


No. 4.—Some Pranarians from the Great Barrier Reef of Australia. By 
W. McM. Woodworth. (1 Plate.) April, 1898 . 


No. 5.— Reports on the Drepecinc Operations off the West Coast of 
Central America to the Galapagos, etc., by the U. S. Fish Commission 
Steamer “ Albatross.” XXIII. Preliminary Report on the Ecuini. By 
A. Acassiz. (13 Plates and Chart.) June, 1898 


No. 6.— The Nervous System of NereIs virens Sars. A Study in Com- 
parative Neurology. By J.J. Hamaxer. (5 Plates.) July, 1898 


No. 7.—On Remains of SrruTHIoLitHUS CHERSONENSIS from Northern 
China, with Remarks on the Distribution of Struthious Birds. By C. R. 
Eastman. (1 Plate.) July, 1898 


No. 8.— Reports on the Dreperne Operations off the West Coast of 
Central America to the Galapagos, etc., by the U. S. Fish Commission 
Steamer “ Albatross.” XXIV. Preliminary Report on BRANCHIOCERI- 
ANTHUs UrcrEotus, a New Type of Actinian. By E. L. Marr. (3 Plates.) 
August, 1898 


No. 9.—Acaterus from the Fis Istanps. By A. Acassiz and A. G. 
Mayer. (17 Plates.) February, 1899 


No. 10.— Reports on the Results of Dredging, under the Supervision of 
ALEXANDER AGASSIZ, in the Gulf of Mexico and the Caribbean Sea, and 
on the East Coast of the United States, 1877 to 1880, by the U. S. Coast 
Survey Steamer “Blake,” Lieut. Commander C. D. Siespep, U. S. N,, 
and Commander J. R. Bartiert, U.S. N., Commanding. XXXVIII. 
Etude Monographique des PLEUROTOMAIRES ACTUELS. Par E. L. Bouvier 
et H. Fiscurer. (4 Plates.) . 


PAGE 


1 


21 


61 


191 


—— 2s. 


ie ee a. 


Bulletin of the Museum of Comparative Zoology 
AT HARVARD COLLEGE. 
Vou. XXX; No. 1. 


STUDIES FROM THE NEWPORT MARINE LABORATORY. 


CoMMUNICATED BY ALEXANDER AGASSIZ. 


No. XLI. 


ON DACTYLOMETRA. 


By ALEXANDER AGASSIZ AND ALFRED GOLDSBOROUGH MAYER. 


Wiru THIRTEEN PLATES. 


CAMBRIDGE, MASS., U.S.A. 
PRINTED FOR THE MUSEUM. 
APRIL, 1898. 


Poks she 
3 


No. 1. — Studies from the Newport Marine Laboratory. Commu- 
nicated by ALEXANDER AGASSIZ. 


XLI. 
On Dactylometra. 


By Avexanper AGassiz AND ALFRED GOLDSBOROUGH MAYER. 


Tue genus Dactylometra belongs to the Pelagide. At the present 
time there are four genera of this family known, and they may be dis- 
tinguished as follows : — 


(1) Pelagia, 8 tentacles, 16 marginal lappets. 
(2) Chrysaora, 24 tentacles, 32 marginal lappets. 
(3) Dactylometra, 40 tentacles, 48 marginal lappets. 


(4) Melanaster, 24 tentacles, 48 marginal lappets. 


Thirteen species of Pelagia and eight of Chrysaora are known, and 
they are found distributed among all of the great oceans of the world. 
There are only two species of Dactylometra, and they are found along 
the Atlantic coasts of North and South America. The genus Mela- 
naster is represented by but one species, M. Mertensii (L. Agassiz, Cont. 
Nat. Hist. U. S., 1862, Vol. IV. pp. 126, 166). It was described and 
figured by Brandt,? and is found in the North Pacific. 

The genus Dactylometra consists of Pelagidee with 40 tentacles (3 
large and 2 small ones between each successive pair of marginal sense 
organs), and with 48 marginal lappets (6 between each successive pair 
of sense organs). 

In Dactylometra quinquecirra the bell is high, being almost hemi- 
spherical in shape. In mature medusz there are five tentacles between 
each successive pair of marginal sense organs (Figs. 2-4, 6). Three of 
these tentacles, the primary and secondary (I, II, I, Fig. 6), arise from 
the clefts between the lappets, and the other two, which we will call 
tertiary tentacles (III, III, Fig. 6), are generally seen arising from the 


1 Brandt, J. F., 1838; Mem. Acad. d. St. Pétersbourg, 6 Série, Tom. IV. p. 
385, Pls. XVI. and XVII. 
XXXII,— No. 1. 


2 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


sub-umbrella floor of the ocular lappets ; for even in very large medusz 
the ocular lappets exhibit only a slight notch, as is seen in oe, oc, Fig- 
‘ure 6, and in Figure 26, Plate X., and only in a very few of the largest 
and most mature medusz do we find the ocular lappets divided so that 
the tertiary tentacles arise from the cleft. This latter condition is shown 
in Figure 19, Plate IX. It is interesting to notice that these tertiary 
tentacles do not make their appearance until the medusa is almost 
mature, when the bell has attained a diameter of 130 mm., and even 
then many of them fail to develop into anything more than mere fila- 
ments of very short length, such as are shown in Figure 4, Plate IV., 
and Figure 27, Plate IX. Indeed they never grow to a greater length 
than is seen in Figure 6, which represents their condition in a medusa 
measuring 190 mm. across the disk. These rudimentary tentacles stand 
in striking contrast with the primary and secondary ones, which, when 
fully extended, attain a length of from three to four times the diameter 
of the disk. 

In common with all other Pelagide, there are eight marginal sense 
organs in Dactylometra ; four of these occupy the primary, and four the 
secondary radii. They are set into little niches in the edge of the bell, 
and project downwards from the oral surface. Figure 7, Plate VIL., 
represents the sense organ as seen from the oral side, and Figure 8 is a 
somewhat diagrammatic longitudinal section, showing the so called 
“olfactory pit” (opt), which projects downwards from the upper surface 
of the bell just above the region of the sense organ. As was long ago 
pointed out by L. Agassiz, these sense organs are morphologically noth- 
ing more than little hollow tentacles, the entoderm of which contains 
a mass of otolythic concretions (con, Figs. 7, 8, and 9). 

The mouth opening (JZ Figs. 6, 31, Plates VI., IX.) is cruciform, 
and occupies the centre of the oral surface of the disk. It is surrounded 
by four oral fringes, or palps, which occupy the secondary radii, and 
when fully expanded attain a length of about three or four times the 
diameter of the disk itself. Fewkes! is mistaken in stating that the 
oral appendages are “ of two kinds, four of which are quite long, floating 
gracefully along after the medusa as it swims in the water. The re- 
maining oral appendages being shorter, more ruffled, and confined to the 
immediate vicinity of the mouth.” He was evidently deceived by 
observing a peculiar state of contraction of the oral fringes, for their 
shape is constantly changing. Sometimes one sees them as beantifully 


1 Fewkes, J. W., 1881; Studies of the Jelly Fishes of Narragansett Bay, p. 178 
Bull. Mus. Comp. Zodl., Vol. VIII. pp. 142-182, 10 Plates. 


ere 


AGASSIZ AND MAYER: DACTYLOMETRA. 3 


fimbricated pennants trailing in long graceful curves far behind the 
medusa, and at other times they are drawn up into a shapeless mass 
about the medusa’s mouth. A view of the free extremity of one of the 
oral fringes is given in Figure 30, Plate XI.; and a good idea of their 
general structure and appearance may be obtained from Figures 1, 2, and 
4. Small wart-like protuberances (Fig. 29, Plate XI.) are found scat- 
tered thickly over the outer surface of the oral fringes; they consist of 
clusters of nematocysts and red colored pigment granules. 

The plan of the stomach is represented in Figure 15, Plate VIII. It 
occupies a large space in the midst of the umbrella, and consists of a 
wide central cavity from which radiate outwards. sixteen simple pockets 
(r, 7’, r, 7’, etc.). These pockets are separated from one another by 
sixteen radiating partitions or septe (rp, Figs. 6, 15, and 35), which 
join the upper and lower walls of the umbrella together. These radial 
partitions contain numerous muscle fibres, by the contraction of which 
the rhythmical movements of the bell are produced. From an inspec- 
tion of Figure 15 it will be seen that eight of the pockets (7,7, r) of 
the stomach lead out into the sense organs, and that the eight others 
(7, r’, r’) lead out into the tentacles ; indeed, the tentacles are hollow 
throughout almost their entire length, and their entoderm is ciliated 
exactly as is that of the stomach itself. 

The genital products are contained in four radially situated infold- 
ings of the oral wall of the stomach, and their position is marked upon 
the oral floor of the disk itself by the four deeply sunken sub-genital 
pits (gpt, Figs. 6, 14, 17, 18, 23, and 25). Figures 14 and 23 are 
somewhat diagrammatic sections of the medusa, intended to show the 
manner in which the genital organs fold inwards into the cavity of the 
stomach. Figure 14, Plate VIII., represents a section through the centre 
of the sub-genital pit and the pocket of the stomach ; while the section 
represented in Figure 23, Plate X., passes through the edge of the sub- 
genital pit, and through the centre of one of the septal partitions. A 
view looking down upon one of the genital organs, the exumbrella being 
removed, is given in Figure 17, Plate 1X. In this figure part of the gen- 
ital epithelium is represented as torn away in order to show the opening 
of the sub-genital pit (gpt) lying below. It will be seen from an in- 
spection of Figures 14, 16, 17, and 23 that the genital organs are fur- 
nished with numerous gastric cirri (ge) which project inwards into the 
cavity of the stomach. A view looking down upon the surface of the 
ovary is given in Figure 34, Plate XI., where we see the immature eggs 
of various sizes attached by peduncles to the ovarian wall. A section of 


4 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


one of these immature eggs, drawn from a specimen killed in Flemming’s 
fluid and stained in Kleinenberg’s hematoxylin, is given in Figure 11, 
Plate VII. The protoplasm is finely granular, the nucleus large and 
vesicular, and the nucleolus contains about half a dozen deeply staining 
highly refractive granules. Figures 12 and 13, Plate VII., represent 
young scyphostome, one of which possesses two and the other four 
tentacles. The older one is 1.5 mm. in height. 

The medusa is provided with two well differentiated sets of radially 
arranged muscle fibres. The principal set is found in the septe of the 
oral surface of the disk (mso, Figs. 6 and 33, Plates VI. and XI), 
and the other set is found in the exumbrella me, me’, Fig. 6, and also 
Figs. 2-4), and alternates in position with the set in the oral septe ; so 
that there are sixteen radial strands of muscle fibres in the sub-umbrella 
alternating with sixteen strands in the exumbrella. It will be seen that 
of the sixteen exumbrella muscle strands, eight (me, Fig. 6) go to the 
sense organs, and eight (me’) to the primary tentacles. 

Clusters of nematocysts are found in the numerous wart-like pro- 
tuberances (Figs. 24 and 29, Plates X. and XI.) which are thickly 

scattered over the exumbrella surface of the disk, the palps, and the 

tentacles. These protuberances are thickly clustered near the centre 
of the disk, where they appear as little hemispherical projections above 
the general surface ; near the outer edges of the disk, however, they are 
elongate itt shape, and at the extreme edge they are again hemispherical 
(see Figs. 19, 26, 28, and 32). If a weak solution of picric acid 
in 50% alcohol is allowed to permeate the sea water in which the 
medusa is living the nematocysts are exploded with great energy. 
Ordinarily they then present the appearance shown in Figure 21, Plate 
IX., but occasionally one finds one resembling that shown in Figure 22, 
where the main shaft of the thread is tightly coiled in a right-handed 
helix, and a small ellipsoidal mass of protoplasm (p) is borne upon the 
free extremity. It is very difficult to imagine how such a thread could 
be turned outward in the ordinary manner, and it is probable that the 
extreme stimulation caused by the picric acid produced an abnormal 
discharge of the nematocysts. The nematocysts which exhibited this 
peculiar structure were invariably immature in development, and were 
only about one tenth as numerous as the ordinary normal ones. 

An idea of the color of the medusa may be obtained from Plates II. 
and III. In some individuals the general color of the disk is yellowish 
with a bluish opalescence, while in others it is decidedly pinkish ; and it 
is interesting to notice that when the pinkish ones have been confined im 


AGASSIZ AND MAYER: DACTYLOMETRA. 5 


an aquarium for a few days they lose their bright color and fade into a 
dull yellow. Indeed, if the medusa be kept in an aquarium without 
food for about six weeks, its disk shrinks to about one eighth of its 
former diameter, and all color fades away until it becomes transparent. 
The aboral surface of the disk is thickly sprinkled over with light ochre- 
yellow spots, caused by protuberances bearing masses of nettling cells ; 
and in addition to these there are sixteen radially arranged regions of 
reddish brown spots, lying just above the radial septz of the stomach 
(see Figs. 2, 3, and 5). These reddish regions usually extend for about 
half way from the periphery of the disk towards the centre, and a closer 
examination shows that they are caused by highly refractive rosin 
colored pigment granules which are contained in the protoplasm of the 
epithelial cells of the disk (see Fig. 20, Plate IX.). In this respect 
indeed, according to McKendrick,’ they are similar to the red pigment 
spots of Chrysaora. The male genital organs are usually decidedly pink 
in color, while the ovaries are often yellowish, or ashy gray. The bands 
of muscles in the radial septe are of a glistening white. The ectoderm 
of the tentacles is ochre-yellow, and the entoderm is often pink. The 
oral fringes are often yellowish, with a delicate shade of opalescent blue 
in certain lights. In other individuals, however, they are of a delicate 
shade of pink, and they are always sprinkled over with red colored 
pigment spots similar to those of the aboral surface of the disk. The 
marginal sense organs are usually white in color. 

The habits of this medusa have already been described by A. Agassiz,” 
who says: “It is somewhat strange that almost all of the Medusx which 
have been observed were found in the brightest sunshine only, or in very 
dark nights. Early in the morning, and until about ten o’clock, even 
on clear days, medusz do not make their appearance, while from eleven 
until one or two o’clock they can be caught in abundance. After this 
time they disappear gradually, and late in the afternoon it is rare to see 
a single jelly-fish. Between nine and ten o’clock they come to the sur- 
face again; and that hour, in fact, is one of the most favorable for col- 
lecting, in spite of the darkness.” When the meduse are confined in 
the stale water of an aquarium they often assume the position shown in 
Plate V., where the disk is flattened out to an extreme degree, the palps 
are spread out over the floor of the aquarium, and the tentacles droop 
listlessly downward. In this position the medusa often remains 


1 McKendrick, J. G.: Coloring Matter of Meduse. Journ. of Anat. and Physiol., 
1881, Vol. XV. pp. 261-264. 
2 North Am. Acal., 1865, p. 49. 


6 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


motionless for a long time, and one is almost forced to compare it with 
a round flat table supported upon numerous legs. 

This medusa makes its appearance on the southern coast of New Eng- 
land at about the first of August. The diameter of the disk is then 
about 50 mm., and there are only three tentacles between each succes- 
sive pair of eye spots, so that it might well be mistaken for a Chrysaora, 
were one unacquainted with its future development. The medusze 
increase both in size and numbers until about the middle of Septem- 
ber, after which time they begin to disappear, although a few may still 
be found as late as the middle of October. The diameter of the disk of 
the full grown medusz is often as great as 250 mm. In common with 
many other Discophore this species seems to prefer the relatively im- 
pure water of bays and narrow estuaries. It is very common in the 
upper reaches of Narragansett Bay near Tiverton, while in the relatively 
purer water of the lower bay it is generally rarer. 

The medusa has also been found at Nantucket (Desor); Naushon 
(A. Agassiz) ; Bermudas (A. 8. Bickmore) ; between the Bermudas and 
the Azores (J. Drayton) ; and a well marked southern variety from Beau- 
fort, North Carolina (W. K. Brooks). 

Two species of fish have been found to accompany this medusa; one 
of these is a Clupeoid, and the other is the young of the common 
Butterfish (Stromateus triacanthus). These fish constantly crowd about 
the medusa, and so persistent are they in following the jelly-fish that 
they often allow themselves to be dipped up in the net along with their 
companion. 

The relations between the fish and the medusa, however, are far from 
symbiotic, for the fish gorge themselves with fragments of the tentacles 
and oral fringes, which they tear off from time to time. The medusa, on 
the other hand, is not wholly unavenged, for every now and then it suc- 
ceeds in stinging to death and devouring one of its persecutors. The 
fish which possess this curious habit are rarely more than an inch in 
length. 

An interesting abnormal specimen of Dactylometra quinquecirra was 
found at Tiverton, Rhode Island, in September, 1896. In this individ- 
ual there were three oral fringes, six genital organs and sub-genital pits, 
twelve marginal sense organs, forty-eight marginal lappets, and thirty- 
six tentacles (three between each successive pair of marginal sense 
organs). 


—— eo CUS 


AGASSIZ AND MAYER: DACTYLOMETRA. 4 


Dactylometra lactea L. Agassiz. 
Plates XII. and XIII., and Fig. 10, Plate VII. 


Chrysaora lactea F. Eschscholtz, 1829; Syst. der Acal., p. 81, Taf. VII. Fig. 3. 

Dactylometra lactea L. Agassiz, 1862; Cont. Nat. Hist. of U. S., Vol. IV. pp. 
125, 126, and 166. 

Dactylometra lactea E. Haeckel, 1879; Das Syst. der Medusen, p. 517. 

Dactylometra lactea R. von Lendenfeld, 1884; Proc. Linnean Soc. New South 
Wales, Vol. IX. p. 271. 


Dactylometra lactea is the type species of the genus Dactylometra, 
which was established by L. Agassiz.? ¢ 

We shall confine ourselves to describing the differences which exist be- 
tween this species and its near ally D. quinquecirra. Figure 35, Plate 
XII., shows a young Dactylometra lactea in the stage where there are 
but four lappets, and five tentacles between each successive pair of sense 
organs. In the mature individual (Fig. 36, Plate XIII.), on the other 
hand, there are six lappets and five tentacles between each two sense 
organs. The tentacles of the mature individuals arise from the notches 
between the lappets. The primary tentacles when expanded may stretch 
out to a length of from two to three times the diameter of the bell. The 
secondary tentacles, however, are only about one half, and the tertiary 
about one quarter, as long as the primary ones. 

The general color of the medusa is a milky white ; and the bell is 
sprinkled over with light ochre-yellow spots, which are clustered thickly 
about the aboral pole. The genital organs are slightly yellowish, and 
a faint purplish iridescence is seen playing over the palps. The sense 
organs are of a brilliant white. A view of one of these sense organs as 
seen from the under side of the bell is given in Figure 10, Plate VII. 

Our figures were drawn from life, from specimens obtained in Havana 
harbor, Cuba, on February 22, 1893, while on the expedition to the 
Bahamas in the yacht “ Wild Duck.” 

It is probable that this medusa is the species found by Eschscholtz in 
the Bay of Rio Janeiro, Brazil. 

The habits of this medusa are remarkable for their extreme regularity ; 
during the morning hours not one of them is to be found, while at about 
four o'clock in the afternoon they suddenly appear in large numbers, 
and remain swimming near the surface until long after nightfall. One 


1 Cont. Nat. Hist. of U. S., 1862, Vol. IV. p. 125. 


8 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


cannot but wonder how these creatures can live, and thrive, in the dis- 
gustingly impure water of Havana harbor. It is, however, well known 
that the Discophore in general seem to prefer the relatively impure 
waters of bays to that of the open ocean. Dactylometra lactea is much 
smaller than its northern ally, D. quinquecirra. Fully developed speci- 
mens measure only 65 mm. across the disk, while the young individual 
figured upon Plate IX. was only 40 mm. in diameter. 


—— 


Fig. 1. 


Fig. 2. 


Fig. 3. 


Fig. 4. 


Fig. 5. 


Fig. 6. 


AGASSIZ AND MAYER: DACTYLOMETRA. ) 


EXPLANATION OF PLATES. 


PLATE I. 


Dactylometra quinquecirra, from a photograph. 


PLATE II. 


Side view of Dactylometra quinquecirra, } natural size. Specimen found 
at Tiverton, Rhode Island. 


PLATE I. 


Aboral view of a mature male Dactylometra quinquecirra, measuring 
190 mm. in diameter. Tiverton, Rhode Island. 


PLATE IV. 


Oral view of Dactylometra quinquecirra. One of the oral fringes is cut 
away in order to expose to view one of the sub-genital pits (see gpt, 
Figs. 5, 13, 16, 17, 22, and 24). From a specimen found at Tiverton, 
Rhode Island, measuring 180 mm. in diameter. 


PLATE V. 


Side view of a Dactylometra quinquecirra which has been confined for 
a considerable length of time in the stale water of an aquarium. The 
bell is greatly flattened and expanded, and the oral fringes and ten- 
tacles lie spread out over the aquarium floor. The specimen here 
represented is in the ‘“‘ Chrysaora” stage of development; i. e. there 
are only three tentacles, and four lappets between each successive pair 
of sense organs. 


PLATE VI. 


Oral view of an octant of the disk of a mature Dactylometra quinquecirra ; 
natural size. The oral fringes are cut off in order to show the shape of 
the mouth opening (J/); gen, genital organs; gpt, sub-genital pit; me 
and me’, muscles of exumbrella; mso, muscles of sub-umbrella ; rp, radial 
partitions of stomach; oc, ocular lappets; ¢, tentacular lappets; I, I, 
Ill, primary, secondary, and tertiary tentacles respectively. 


10 

Ripe 7. 
Fig. 8. 
Fig. 9. 
Fig. 10. 
Fig. 11. 


BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


PLATE VII. 


Sense organ of Dactylometra quinquecirra, as seen from the oral side of 
the disk. 

Longitudinal section of the sense organ. opt, “ olfactory ” pit; con, oto- 
lythic concretions ; ect, ectoderm; ent, entoderm. 

Otolythic concretions from the sense organ of Dactylometra quinquecirra. 

Oral view of sense organ of Dactylometra lactea. 

Section of immature egg from ovary of Dactylometra quinquecirra. 


Figs. 12 and 13. Young scyphostome of Dactylometra quinquecirra, with two and 


Fig. 


Fig. 


Fig. 


ig. 17. 


ig. 18. 
LQ. 


14. 


15. 


16. 


e. 20. 


, 21. 
. A young and probably immature nematocyst exploded under the stimulus 


pals 
. 28. 


four tentacles respectively. 


PLATE VIII. 


Longitudinal section of Dactylometra quinquecirra through the centre of 
two of the sub-genital pits. gc, gastric cirri; gpt, sub-genital pit. 

Plan of the stomach of Dactylometra quinquecirra. 7, r’, 7, 7’, pockets of 
the stomach; rp, rp, radial partitions of stomach. 


PLATE IX. 
Dactylometra quinquecirra. 


View looking down upon a small portion of the genital organs to show 
gastric cirri (gc). 

View looking down upon one of the genital organs, the exumbrella being 
removed, and part of the genital epithelium being torn away in order to 
expose the opening of the sub-genital pit (gpt). j 

Side view of oral fringes facing a primary radius. 

Aboral view of ocular lappets and tertiary tentacles. Showing the ten- 
tacle arising from a cleft in the lappet. 

Section 6.6u thick, through one of the red pigment spots of the exumbrella 
surface of the disk. The pigment appears as small highly refractive 
rosin colored granules in the protoplasm of the epithelial cells. Nema- 
tocystic capsules of various sizes are situated between the epithelial cells. 

An exploded nematocyst. 


of picric acid. 
PLATE X. 


Dactylometra quinquecirra. 


. Longitudinal section through edge of sub-genital pit and centre of one of 


the radial septe of the stomach. 


. One of the wart-like protuberances of the exumbrella surface of the disk, 


showing pigment granules and clusters of nematocysts. 


. Side view of oral fringes seen facing a secondary radius. 
. View of ocular lappet and tertiary tentacle, showing a slight cleft in the 


lappet. 
Enlarged view of the tertiary tentacle shown in Figure 26. 
Oral view of primary tentacle. The tentacle is hollow. 


es eee 


ee eEEeEeEeEEEeEOEeEeEEE———eE————————EE ee 


—_ 


Ol —— 


Fig. 29. 
Fig. 30. 
Fig. 31. 
Fig. 32. 
Fig. 33. 


Fig. 34. 


Fig. 35. 


Fig. 36. 


AGASSIZ AND MAYER: DACTYLOMETRA. fs 


PLATE XI. 
Dactylometra quinquecirra. 


One of the wart-like protuberances, consisting of nematocystic capsules 
and pigment cells, found upon the oral fringes. 

Free extremity of one of the oral fringes. 

Oral fringes cut off to show shape of mouth opening (J/). 

Aboral view of primary tentacle showing also dark-red pigment spots 
on disk. 

Oral view of radial septum (7p) of the stomach. mso, muscles in radial 
septum. 

View looking down upon genital epithelium of ovary showing mode of 
attachment of eggs of various sizes. 


PLATE XII. 


Side view of a young Dactylometra lactea. There are only 4 lappets be- 
tween each successive pair of sense organs, insteag of 6, as in the mature 
medusa. 14;°, natural size. 


PLATE XIII. 


Oral view of a mature Dactylometra lactea. Natural size. 


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Bulletin of the Museum of Comparative Zodlogy 
AT HARVARD COLLEGE. 
Vout. XXXII. No. 2. 


ON SOME MEDUSZZ FROM AUSTRALIA. 


By ALEXANDER AGASSIZ AND ALFRED GOLDSBOROUGH MAYER. 


4 


Witu THREE PLATES. 


CAMBRIDGE, MASS., U.S. A.: 
PRINTED FOR THE MUSEUM. 
Aprit, 1898. 


No. 2.— On some Meduse from Australia. By ALEXANDER 
AGASSIZ AND ALFRED GOLDSBOROUGH MAYER. 


Tue meduse described in the following paper were obtained while 
accompanying Mr. Agassiz during his recent visit to the Great Barrier 
Reef of Australia in April and May, 1896. Our course lay along the 
Queensland coast between the Great Barrier Reef and the mainland as 
far north as Lizard Island. Unfortunately, the season of the south- 
east Monsoon is far from favorable for collecting pelagic animals, as 
the winds blow a brisk gale almost incessantly and the water is much 
disturbed. 

The few hauls of the surface net were all very similar, and brought to 
light large numbers of Sagittze and Copepods, and a few Appendicularia, 
Doliolum, and Decapod larve. The only Celenterates found were 
several specimens of a Rhegmatodes, and a Mertensia. Two Dis- 
cophore were found during our cruise. One of these is a new species, 
for which we propose the name Desmonema rosea, and the other is 
Crambessa mosaica Haeckel. 


Desmonema, rosea, nov. sp. 
Plate I. Fig. 1. 


The genus Desmonema was established by L. Agassiz.1_ It contains Cyaneide 
with eight sense organs, and numerous tentacles which are arranged in eight 
bunches arising from the sub-umbrella. The tentacles of each of these bunches 
are arranged, one after the other, in a single row. The margin of the bell 
possesses eight principal lappets and sixteen to thirty-two secondary lappets. 

An oral view of Desmonema rosea is given in Plate I. Figure 1. The bell is 
rather flat, being about twice as broad as it is high. The eight primary lappets 
are separated from one another by deep clefts, which extend inwards for about 
a quarter of the distance from the margin of the bell towards the centre. There 
are thirty-two small, smoothly rounded, secondary lappets. 

The eight marginal sense organs are sunken in long narrow niches lying in 
the oral floor of the sub-umbrella. 

The tentacles are arranged in eight crescent-shaped rows, lying between and 
alternating with the eight primary lappets of the disk. There is but a single 
row of tentacles in each of these crescents. 


1 Agassiz, L., 1862; Contrib. to Nat. Hist. of U. S., Vol. IV. p. 166. 
VOL. XXXII. — NO. 2. 


16 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


The muscles of the oral surface of the disk are very conspicuous, and are 
arranged in sixteen bi-forked bundles, containing both circular and radial 
muscle fibres. The bundles lying adjacent to the tentacles are about twice as 
broad as those that lie near the sense organs. 

The genital organs protrude from the oral surface of the disk as four com- 
plexly fimbricated sacs. The four oral fringes are very wide, and their free 
edges are sharply folded. 

The general color of the substance of the disk is a delicate opalescent yellow, 
reminding one of the medieval glass of Venice. The muscle system of the oral 
wall of the bell is of a delicate pink, as are also the genital organs. The oral 
fringes are of a most exquisite and delicate rose-color, and the entoderm of the 
tentacles is port-wine colored. The sense organs bear an intense orange pig- 
ment. The diameter of the disk is 180mm. The medusa was found swim- 
ming in great numbers in Largs Bay, near Adelaide, South Australia, on May 
29, 1896. 

This species is similar in some respects to Cyanea Muellerianthe, that was 
described by Haacke! from the Gulf of St. Vincent. C. Muellerianthe is, 
however, smaller than Desomnema rosea ; the shape of the marginal lappets 
and muscle bands is different, and, above all, there are several rows of ten- 
tacles in each crescent, instead of a single row, as is characteristic of the 
genus Desmonema. It also bears some resemblance to Cyanea annaskala, von 
Lendenfeld.? 


Crambessa mosaica Haeckel. 
Plates II. and III. 


Cephea mosaica Quoy et Gaimard, 1824; Voyage de l’Uranie, Zoologie, p. 569, 
Plate 85, Fig. 3. 

Rhizostoma mosaica F. Eschscholtz, 1829; System der Acalephen, p. 53. T. H. 
Huxley, 1849; Phil. Trans. Roy. Soc., pp. 422, 452, Plate 38 (Figs. 26, 27), 
Plate 39 (Figs. 28-34). 

Catostylus mosaicus L. Agassiz, 1862; Contrib. to Nat. Hist. of U. S., Vol. IV. p. 
152. Grenacher und Noll, 1876; Abhandl. Senckenberg. Ges., Bd. X. p. 38. 

Catostylus Wilkesii L. Agassiz, 1862 ; Contrib. to Nat. Hist. of U.S., Vol. IV. p. 152. 

Crambessa mosaica E. Haeckel, 1879; Das System der Medusen, p. 622. R. von 
Lendenfeld, 1883; Zeitschrift fiir Wissen. Zool., Bd. XX XVIII. p. 635. R. von 
Lendenfeld, 1884; Proc. Linn. Soc. New South Wales, Vol. IX. Part IT. p. 299. 
R. von Lendenfeld, 1884; Proc. Linn. Soc. New South Wales, Vol. IX. p. 926; 
Medusze of the Australian Seas, Part I. p. 30, Sydney, 1887. Zeit. fiir Wissen. 
Zool., 1888, Bd. XLVII. Heft 2, pp. 218, 281-242, Pls. 19, 21, 23-27. 


Although so much has been written concerning the anatomy and histology 
of this medusa, no figure of it has as yet been given, if we except the sketch 
by Quoy and Gaimard in the Voyage de l’Uranie, Plate 85, Fig. 3. We there- 


1 Haacke, W., 1887; Jenaische Zeitschrift, Bd. XX. pp. 605-614, Plate 36. 
2 R. von Lendenfeld, 1882; Zeit. Wiss. Zool., Bd. 37, p. 465, Pl. 27-33. 


AGASSIZ AND MAYER: MEDUSA FROM AUSTRALIA. 17 


fore give a figure on Plate II., and a few details of its structure on Plate IIL., 
and also a brief description of the Medusa. 

When fully expanded the bell is rather flat, being five or six times as broad 
as it is high. The aboral surface is thickly covered with small granular 
papille, which give it a roughened appearance. The marginal lappets are very 
numerous, and their number is not very constant, but there are usually 16 
between each pair of sense organs, and as there are 8 sense organs, it would 
seem that the normal number of lappets is 128. 

An aboral view of one of the marginal sense organs is given in Figure 3, 
Plate III. An excellent figure of a longitudinal section has been given by 
von Lendenfeld (’88, p. 269, Fig. 66). 

Four thick pillars extend downwards from the ventral surface of the bell, 
and support the brachial disk, or subgenital porticus, as it is often called. The 
brachial disk, in turn, bears the eight mouth-arms (von Lendenfeld, ’88, p. 
239, Taf. 19, Fig. 10). A drawing of one of these mouth-arms is given in 
Figure 5, Plate III.; and it is lettered to correspond with von Lendenfeld’s 
Figure 36, Plate 23. The short, simple, upper portion of the arm is indicated 
by e, and a, 6, and d show the three wings of the lower arm; a being 
ventral, and 6 and d dorsal. A cross section of the lower portion of the arm 
taken at niveau ss, Figure 5, is given in Figure 6. Its lettering is similar to 
that of Figure 5. A view of the terminal portion of one of the mouth-arms 
showing the suctorial mouths, surrounded by double rows of small tentacles, is 
given in Figure 4. In life these tentacles keep in incessant motion, and by 
this means small particles of food are swept into the numerous suctorial 
mouths which open at intervals between the rows of tentacles. Good de- 
scriptions of the mouth-arms will be found in the papers of Grenacher and 
Noll (76),1 and of Hamann (’82).? 

The color of this medusa is normally cobalt-blue, but, as was discovered by 
von Lendenfeld (’84, p. 925), a species of Zodxanthella commonly infests it, 
forming dense clusters throughout the jelly ; and when this is the case the 
blue color is lost, and the medusa changes to a brown color, varying from that 
of white bread to that of coffee. Our figure (Plate II.) shows one of these in- 
fested medusz, and it will be seen that the only trace of the normal color is 
found in a faint blue line marking the uppermost regions of the suctorial 
mouths of the mouth-arms. In the estuary of the Brisbane River on May 21 we 
saw a great number of these meduse nearly every one of which was of a deep 
cobalt-blue, while now and then one was seen almost white in color, and still 
others showed intermediate stages between the deep blue and the white. We 
found the white or slightly brownish medusz in the Hawkesbury River near 
Sydney on April 4; in the harbor of Cairns, Queensland, April 27; and in the 
Brisbane River, May 21. We also found a small dark brown or coffee-colored 


1 H. Grenacher und F. C. Noll, 1876; Abhand. d. Senckenberg. Naturf. Gesell., 
Vol. X. p. 146, Plates I., IIT.-VII. 
2 O. Hamann, 1882; Jen. Zeit. fiir Naturwis., Vol. XV. pp. 243-285, 3 Plates. 


18 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


specimen at Lark Opening, near Cooktown, Queensland, on May 4. The 
medusa has been found by von Lendenfeld in the harbors of Sydney and 
Melbourne. In Melbourne Harbor the specimens are blue, while in Sydney 
they are universally brown or coffee-colored (von Lendenfeld, ’88, p. 241). 
The medusa is evidently common all along the eastern coast of Australia, 
where it congregates in large numbers in the harbors and brackish estuaries. 

Von Lendenfeld found a small species of fish, Trichiurus declivis Jenyns, in 
“symbiosis ” with the medusa in Sydney Harbor. We found the same species 
accompanying the medusz collected in Cairns Harbor, Queensland. 

The diameter of the disk of full grown meduse is about 250 mm. 


Hig: 1. 


Fig. 2. 


AGASSIZ AND MAYER: MEDUSA FROM AUSTRALIA. 19 


EXPLANATION OF THE PLATES. 


PLATE I. 


Desmonema rosea; oral view ; + natural size. 


PLATE II. 


Side view of Crambessa mosaica ; 2 natural size. 


PLATE III. 
Crambessa mosaica. 


Aboral view of marginal sense organ. 


. Side view of the terminal portion of one of the mouth-arms, highly magni- 


fied, showing the suctorial mouths and the furrows bordered by rows of 
tentacles. 
Side view of a mouth-arm. 


. Cross section of one of the mouth-arms. 


. 
ee 


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AUSTRALIAN MEDUSAE 


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Bulletin of the Museum of Comparative Zodlogy 
AT HARVARD COLLEGE, 
Vou. XXXII. No. 3. 


THE GORDIACEA OF CERTAIN AMERICAN 
COLLECTIONS. 


WITH PARTICULAR REFERENCE TO THE NORTH AMERICAN FAUNA. 


By Tuomas H. Montcomery, Jr. 


WitH FIFTEEN PLATEs. 


CAMBRIDGE, MASS., U.S. A.: 
PRINTED FOR THE MUSEUM. 
AprIL, 1898. 


* | ¥ 
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; 


si Puy's ed 


Pi oli 
Cas 
: 


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La AAP 


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eh 


No. 3.— The Gordiacea of certain American Collections with par- 
ticular Reference to the North American Fauna, By THoMaAs 
H. MonTGoMERY, JR. 


Ir has been the intention of the author to pursue certain anatomical 
studies on Gordius and its allies, but this object could not be immedi- 
ately carried out owing to lack of material, and also to the difficulty 
encountered in determining the American species. Accordingly it seemed 
advisable to describe the American species systematically before entering 
upon an anatomical study of them. It is very apparent that the North 
American Fauna is very rich in species of Gordiacea, and yet the inves- 
tigation of these interesting forms has been almost wholly neglected 
by American zodlogists, Joseph Leidy being thus far almost our only 
writer upon them; and more species are known from South than from 
North America. 

The material for this study was mainly derived from three collections. 
The Leidy collection, which is the property of the University of Pennsyl- 
vania, is the richest of these, and contains some of Leidy’s types; my 
thanks are due to Dr. Charles W. Stiles of the Smithsonian Institution 
for having kindly forwarded this collection. I would express my obliga- 
tions to Dr. Alexander Agassiz for permission to examine the excellent 
collection of the Museum of Comparative Zodlogy at Harvard ; and to 
Dr. W. M. Woodworth for his trouble in sending me this collection. My 
thanks are further due to Dr. Stiles for specimens from his own and 
from the Smithsonian collection ; and for other specimens to the following 
gentlemen: Prof. E.G. Conklin, University of Pennsylvania ; Prof. Thos. 
H. Morgan, Bryn Mawr College; Mr. E. G. Vanatta, Academy of Natural 
Sciences, Philadelphia; and to Mr. Satterthwaite of Westtown, Pa. 
Further, I would express my thanks to the curators of the Academy 
of Natural Sciences, Philadelphia, for the opportunity to examine the 
specimens in this collection. In a previous paper, to appear in April, 
1898, in Spengel’s “ Zool. Jahrbiicher,” I described two new exotic spe- 
cies from American collections. 

VOL. XXXII. — NO. 3. 1 


24 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Certain of the new species here described were based upon the exam- 
ination of a single specimen, but of most of them several individuals 
were studied. It is, in my opinion, less adducive to confusion of nomen- 
clature to preliminarily separate aberrant forms, even though only single 
specimens are known, than to class them all under one name. This 
group of worms is difficult of study, the external specific characters are 
few, and it appears that it is a group in which many of the species are 
in process of transformation, judging from their amount of variability. 
Then there are sometimes sexual differences, as well as differences at 
various times of life. Bearing these points in view, I have laid par- 
ticular stress upon the following systematic characters: the superficial 
markings of the cuticle, which have been shown by Villot to present 
exceedingly valuable and reliable characters, though even the surface of 
the cuticle is in many forms subject to individual variation ; the form of 
the posterior end in both sexes ; and, though this is not as reliable as 
the preceding character, the form of the anterior end. The presence of 
median dorsal or ventral grooves along the surface of the body is a less 
reliable character, and still less so is the coloration. The males are 
more easily determined than the females; the form of the tail lobes in 
Gordius and the presence or absence of hairs or spines in their neighbor- 
hood are of much importance ; but in the genius Ohordodes the form of 
the posterior end of the male is much more uniform than in the males of 
the former genus. 

A historical review of the previous researches upon the American 
species will be followed by the descriptions of the species examined. 


A. HISTORICAL REVIEW. 


1847. Creplin described Chordodes parasitus, n. sp., from a Brazilian 
Acanthoditis, but his brief description is altogether insufficient for pur- 
poses of identification. 

1849. Gay described from Valparaiso, Chile, a Gordius ( G. chilensis) 
as follows: “ Gordius gracilis, cinereo-fuscus, obscurus ; capite nigro.. . 
es de color pardo morenusco oscuro, con la estremidad anterior del cuerpo 
6 la region cefalica negra ; en los manchos la porcion posterior se bifurca 
mucho.” I agree with Camerano (’90) that this diagnosis is wholly 
insufficient. 

1850. Leidy briefly refers a Gordius seen by him to the European 
G. aquaticus. 


MONTGOMERY: GORDIACEA. 25 


1851. Leidy describes G. varius, n. sp., which is distinguished from 
G. aquaticus in that “ the caudal extremity of the female is trifurcated, 
while that of the European species is blunt. The length is from 4 to 
12 inches. Of this species there are several varieties from different 
localities, which may upon further examination prove to be distinct spe- 
cies. . . . A second species of Gordius was obtained by Professor Baird 
from a spring in Essex County, New York. It is much more deli- 
cate than the former, and from 5 to 7 inches long. The female caudal 
extremity is blunt. The male caudal extremity is bifurcate and fringed 
with peculiar epidermoid appendages. For this second species the name 
Gordius lineatus was proposed.” In the same year Diesing writes of 
G. chordodes, n. sp.: “Corpus longissimum teretiusculum crassum rigi- 
dum, fusco-brunneum. Caput apice rotundatum. .. . Habitaculum. 
Acanthodis glabrata: in cavo abdominis, in Brasilia (Beschke). Spe- 
-cimen identicum femineum ex aqua in Brasilia hausit (Natterer).” 
Diesing’s species is not sufficiently characterized. 

1853. Baird mentions two new species from North America, of which 
the first is a good species: G. platyura,n.sp.: “ Body of a uniform dull 
white color, quite smooth, with a depressed line on one side throughout 
its whole length, obscurely ringed at unequal distances, narrower at the 
anterior extremity and terminating in a broad, flattish tail, which is 
slightly bifid. Length of animal 32 inches, breadth of middle of body 
about 4 a line; tail 1 line broad. Jamaica?” G. fasciatus, n. sp.: 
“Kpidermis granulated. . . . Body smooth, skin prettily shagreened 
with very fine lines crossing each other in opposite directions, of a light 
color banded with broad patches of dark brown. Anterior extremity 
smaller than posterior, and roughened with raised circular ridges, which 
extend for about three lines, and as well as posterior extremity of a very 
dark color, almost black. Length 114 inches, breadth about 1 milli- 
meter.” This was a female from North America. I regard this descrip- 
tion of G. fasciatus as wholly inadequate for purposes of identification, 
and on this account judge that Rémer (’96) is in error in placing it 
as a synonyme of G. aquaticus Linn. Leidy (’53) mentions Gordii of 
a milk-white color as very common in grasshoppers in the vicinity of 
-Philadelphia. 

1855. Mébius gives a good description of Chordodes pilosus, n. sp. 
from Venezuela ; though he confused the head end with the posterior 
extremity: length 212 mm., “er . . . nahm aber wihrend neun Tagen, 
die er noch im Wasser, sich triige bewegend, lebte, um 259 mm. zu, so 
dass seine Linge, als er todt war, 471 mm. betrug”; tail end swollen, 


26 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


cloacal opening large, circular. Head laterally compressed, somewhat 
pointed ; cuticle with irregular prominences, which are figured. Or, in 
the words of his own diagnosis: “Corpus nigrum verrucosum, medio 
cylindricum, utrinque attenuatum depressumque, linea ventrali et dorsali, 
quarum parti caudali fasciculi pilorum insiti. Caput ellipsoideum, con- 
cavitate frontali. Extremitas caudalis trigona, apice rotundata.” This 
is a good species. 

1856. Leidy gives a much fuller description of his G. varius. He 
also describes G. robustus, n. sp., and places synonymous with it G. seta 
Miill., and G. lineatus Leidy. 

1857. The same author mentions a collection of 48 Gordit, 525 miles 
west of Fort Riley, Kansas. 

1858. Leidy notes the occurrence of an embryo of G. varius in Lum- 
briculus limosus. 

1861. Diesing regards G. platyurus and fasciatus Baird as good 
species; as also G. varius Leidy, with which he considers synonymous 
the “ G. aquaticus” of Leidy, 51. He considers Leidy’s neatus and 
robustus as doubtful synonymes of G. seta Miill. (aguatieus Linn.), Die- 
sing also describes G. swbspiralis, nu. sp.: “Corpus maris brunneum, 
femine antrorsum attenuatum, lete brunneum, nitidum, iridescens. 
Caput annulo obscure brunneo cinctum. Extremitas caudalis maris 
subspiralis crucibus furce terminalis divergentibus, incurvatis, levibus, 
plica membranacea semilunari ad basin junctis, femine obtusa, subcom- 
pressa. .. . In palude cum Siredonibus, copiose, in territorio Kansas 
(Hammond@).” 

1866. Schneider regards G. varius Leidy as a possible synonyme of 
G. gratianopolensis Charvet ( G. tricuspidatus Meissn.). 

1874, Villot regards the following as good species: G. lineatus, 
robustus, and varius of Leidy; G. subspiralis and G. chordodes of Diesing ; 
and G. chilensis Blanchard. He describes the following new species from 
America: — G. @neus, n. sp.: “Extrémité antérieure tronquée, légere- 
ment renfiée. Ouverture ano-génitale du male entourée d’un anneau 
brun. Lobes bien développés, séparés par un assez large intervalle. 
Brun bronzé. (Les jeunes individus sont d’un blanc jaunatre uniforme.) 
Epiderme divisé en losanges par un réseau de lignes saillantes oblique- 
ment croisées’’; from Cumana, Venezuela. G. reticulatus, n. sp.: ‘ Ex- 
trémité antérieure terminée en pointe aigué. Diamétre du corps allant 
en grossissant de l’extrémité antérieure & l’extrémité postérieure, qui 
se termine en point tronqtiee. Ouverture ano-génitale large. Brun 
marron. Une bande dorsale et une bande ventrale d’un brun plus 


MONTGOMERY: GORDIACEA. 27 


a 


foncé. Epiderme aréolé. Aréoles formant un réseau 4 mailles irré- 
guliéres et inégales, ayant en moyenne 10 milliemes de millimétre. 
Une bordure simple de petites papilles autour des aréoles. . . . Cali- 
fornie.” G. prismaticus, n. sp.: “Gréle et aplati. Extrémité posté- 
rieure bilobée. Brun pale. Epiderme aréolé. Aréoles prismatiques et 
hexagonales, ayant environ 10 milliemes de millimetre de haut sur 6 
milliémes de millimétre de large. Quelques papilles tres-petites et tres- 
espacées. . . . Nouvelle-Grenade. Prairie du plateau de Bogota, par 
2,600 métres d’altitude.” He also describes G. deshayes?, nu. sp. from 
Venezuela. 

1879. Weyenbergh gives inadequate descriptions of the following new 
species from South America: G. tenuis, dubius, and acridiorum. In the 
same year Leidy gives a good description of his G. robustus, based on 
specimens from Maryland. 

1881. Oerley regards the following American forms as good species : 
G. fasciatus and platyurus Baird, G. eneus and trilobus of Villot. 

1885. Jeffrey-Bell mentions G. verrucosus Baird, from Vera Paz, Gua- 
temala, and from Costa Rica. 

1887. Villot considers G. subspiralis Dies. as a synonyme of G. aqua- 
ticus Duj.; and adds: ‘Il se peut aussi que le Gordius robustus de 
Leidy et mon Gordius reticulatus, établis sur des échantillons recueillis 
en Amérique, ne soient que des synonymes du Gordius violaceus de 
Baird. 

1890. Camerano considers as doubtful species G. chilensis Gay, tenuis 
and dubius Weyenbergh, and parasitus (Creplin), and considers that 
G. acridiorum Weyenbergh is either a Mermis or Filaria. According to 
him Villot’s three species, G. @neus, deshayesi, and prismaticus, are ten- 
able, and he gives a description of a female specimen of G. eneus. 

1892. Camerano describes a male of G. paranensis, n. sp. from Pal- 
meira (Parana). 

1893. The same writer says of the occurrence of G. verrucosus Baird 
in North America, as reported by Jeffrey-Bell, “Je crois qu'il serait 
nécessaire de faire une révision des spécimens américains rapportées a 
cette espéce.” He also mentions a specimen of G. varius Leidy, from 
Monterey, Mexico, and states “mais on peut douter ... que ces 
caractéres soient suffisants pour distinguer le G. varius du G. tricuspi- 
datus L. Dufour (G. gratianopolensis Diesing, Villot).” Janda describes 
a male of Chordodes brasiliensis, n. sp. from Brazil. 

1894, Goeldi mentions the occurrence of the preceding species in 
Brazil. Camerano describes the following new species from Paraguay 


28 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


and the Argentine Republic: G. alfredi, danielis, and peracce ; and also 
describes female specimens of prismaticus Villot and paranensis Camer. 

1895. Camerano describes males of G. latastei, n. sp. from Santiago, 
Chile. Romer describes Chordodes variopapillatus, n. sp. from Brazil; a 
female of G. violaceus Baird from Arizona, a male of G. aquaticus Linn. 
from Brazil, and a female of the same species from Chili. 

1896. Romer, in his excellent revision of the Gordiacea, regards the 
following American species as tenable: G. platyurus Baird, eneus Villot, 
paranensis Camer., Ohordodes brasiliensis Janda, Chordodes pilosus 
Mobius, and C. variopapillatus Romer; the following as synonymes 
of G. aquaticus Linn.: robustus and lineatus Leidy, fasciatus Baird, sub- 
spiralis Diesing; G. reticulatus Villot as a synonyme of G. violaceus 
Baird ; and the following species as untenable: G. chilensis Blanchard, 
prismaticus Villot, Chordodes parasitus Creplin, G. parasitus Diesing, 
G. deshayesi Villot, and G. verrucosus Baird. According to Romer, 
Gordius varius Leidy becomes Chordodes varius Leidy. In this year 
Camerano describes Chordodes balzani, n. sp. from Bolivia. 

1897. Camerano (’97*) mentions specimens of G. obesus Camer. from 
Santiago and Gualaquiza, and of Chordodes bouviert Villot from Guala- 
quiza ; and also describes males of C. feste, n. sp. from Cuenca. In a 
second paper (’97") he describes C. talensis, n. sp. from Bolivia ; he notes 
G. alfredi Camer. from Tala, G. varius Leidy from Bolivia, and C. peracce 
from Tucuman ; and he further describes male and female specimens of 
C. brasiliensis Janda from §. Lorenzo and Tala. 


CRITIQUE, 


There is considerable confusion in regard to the tenability of certain 
of the preceding American species, mainly due to insufficient diagnoses, 
so that it is necessary to relinquish some of them. Those species which 
are insufficiently described, and hence untenable, are in my opinion the 
following: Chordodes parasitus Creplin (’47), Gordius chilensis Gay 
(Blanchard) (’49), G. aqguatieus Leidy (50), G. chordodes Diesing (’51), 
G. tenuis, dubius, and acridiorum of Weyenbergh (79). G. fasciatus 
Baird (’53) seems also inadequately described. The description of G. sub- 
spiralis Diesing is sufficient for identification, though in the descriptive 
part of this paper we shall find it to be possibly synonymous with G. 
aquaticus robustus (Leidy). Leidy’s description (’51) of his G. lineatus 
is really insufficient ; but this species is nevertheless tenable, since | 
had opportunity to examine the type specimens, and have found them 
to differ from any other species of Gordius. G. reticulatus Villot (’74) 


MONTGOMERY: GORDIACEA. 29 


seems to be also untenable, though it may correspond to G. violaceus 
Baird, as is supposed by Villot (’87) and by Romer (’96); Villot’s 
G. deshayesi, eneus, and prismaticus seem to me to be also doubtful, 
though the last two may be preliminarily retained, since Camerano 
has found further specimens which appear to agree with them. Rodmer 
has given good reasons to show that G. verrucosus Baird is too poorly 
described to be tenable; and there is the greater reason for relinquishing 
this species, since Camerano (’93) has described under the same name 
a form which appears to be a Ohordodes,; hence this name must be 
dropped from the American fauna, if not altogether from the nomen- 
clature of the Gordiacea. Leidy’s (56, 79) descriptions of his G. 
robustus are sufficient for purposes of identification, though in the 
descriptive part of our paper I shall rank this form as a subspecies of the 
European G. aqguaticus Linn. 

There remain then the following species from the American continents 
which appear tenable: Gordius varius Leidy, G. robustus Leidy, G. line- 
atus Leidy, G. platyurus Baird, G. eneus Villot, G. paranensis Camer., 
G. alfredi Camer., G. danielis Camer., G. latastei Camer., G. obesus 
Camer. ; Chordodes pilosus Mobius, C. brasiliensis Janda, C. peracce 
Camer., C. variopapillatus Romer, C. balzani Camer., C. bouviert Villot, 
C. feste Camer., and C. talensis Camer. Thus all of the species described 
by Camerano appear tenable, but since most of his descriptions are unac- 
companied by figures the reidentification of them is rendered very diff- 
cult. The following species are to be regarded as doubtful, if not 
even needing elimination: G. fasciatus Baird, G. prismaticus Villot, 
G. deshayest Villot, and G. verrucosus Baird. 

It seems to be questionable whether the specimens of G. violaceus 
Baird and G. aquaticus Linn., described by Romer from Arizona and 
South America respectively, really belong to these species; but this 
point will be more fully criticised in our description of G. aquaticus 
robustus (Leidy), and of the two new species, G. platycephalus and G. 
densareolatus. 

In the following descriptions, unless otherwise specified, it will be 
understood that the cuticle has been examined on surface preparations 
and sections in Canada balsam. 


30 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


B. DESCRIPTIONS OF THE SPECIES EXAMINED. 


1. Gordius aquaticus robustus (Leidy). 
Plates 1, 2, and Figs. 13, 16-19 of Plate 3. 


G. robustus Leidy, ’56, 779. 

G. subspiralis Diesing, 61. 

G. robustus Leidy, Villot, ’74. 

2 G. violaceus Baird, Villot, ’87. 

2 G. aquaticus Linn., Romer, 795, 796. 


(Leidy’s ’79, types ; Leidy coll. no. 5056, Coningo, Maryland.) 

Form. 'The male more slender than the female, in both sexes the body of 
approximately the same diameter in its whole extent. Head end (Figs. 2, 6, 9, 
10, 11, 17) usually obtuse, especially in the male (Figs. 2, 6, 10), sometimes 
somewhat conical in the female (Fig. 17). Occasionally a slight neck constric- 
tion is present. Usually no median longitudinal grooves are to be seen. In 
some of the larger specimens, especially the females, the whole body is very 
much flattened, and these are apparently individuals which have discharged 
their ova. The posterior end of the female is obtusely truncated (Figs. 7, 8), 
with a faint vertical groove on the termiual aspect; the cloacal aperture is 
terminal, and lies in this groove. Figures 9, 10, show depression on the 
terminal face of the head. 

The posterior end of the male is spirally inrolled (a character of the males 
of all the Gordiacea examined), and is furcate. The tail lobes (Figs. 1, 3-5, 19) 
are short, nearly cylindrical on cross section except that they are somewhat 
concave on their medio-ventral surface, and divergent. The cloacal open- 
ing is round and situated anterior to the point of bifurcation of the lobes. 
On the ventral side of the anterior ends of the tail lobes is situated a more or 
less crescent-shaped transverse cuticular ridge, with posteriorly directed con- 
cave edge. This sharp cuticular ridge is postcloacal. Short branching hairs 
occur on the surface of the tail lobes as elsewhere on the surface of the body, 
but no spicules ; and there is no particular arrangement of the hairs in the 
vicinity of the cloacal aperture. 

Cuticle (Figs. 12, 18, 16). True areoles are absent. In most of the speci- 
mens, and especially well marked in the males, the surface of the cuticle is 
marked by very fine intersecting lines, and, at greater distances apart, by 
broader intersecting raised ridges, which are strictly parallel to the finer lines 
which lie in the rhombic spaces demarcated hy them, and which themselves 
are formed of bundles of fine lines. These larger ridges are seen with low 
powers of magnification, but higher powers are necessary in order to detect the 
system of finer lines which lie between them. On the cuticle, especially abun- 
dant at the ends of the body, are also seen short, thick, and branching hairs. 


MONTGOMERY: GORDIACEA. eA 


Color. Variable according to age, and apparently also according to locality. 
The body varies from a yellowish white to a yellowish brown, or a light 
chocolate-brown ; the males are usually darker than the females, The tip of 
the head is white, and behind it a broad reddish brown ring is to be seen in 
most specimens (not present in some females from Kansas). In all the females 
a more or less intense reddish brown ring immediately encircles the cloacal 
aperture ; and in some specimens there is a narrower, lighter ring outside of 
and separated from the former. In the male a similar dark ring encircles the 
cloacal opening, at a little distance from it ; and a spot of deep brown may lie 
at the posterior edge of this ring : the postcloacal cuticular ridge is brown, its 
posterior edge a much darker reddish brown. 

Dimensions. Largest male, 655 mm. ; greatest diameter, 1.3mm. Largest 
female, length 705 mm.; greatest diameter, 1.9 mm. The males are more 
slender and usually somewhat shorter than the females. The individuals from 
the western United States (Montana, Kansas) averaged considerably longer 
than any eastern specimens examined. 

Comparison. This species has been placed by me as a subspecies of G. aqua- 
ticus Linn., since the differences do not warrant ranking it as a separate species. 
It differs from the true European aquaticus in these points : the presence of a 
dark ring around the female cloacal aperture, the absence of a row of hairs 
around the male cloacal aperture, and the absence of white spots (“ helle 
Flecken”) on the cuticle. 

Especial Diagnostic Characters. The approximately equal diameter of the 
whole body, with the obtuse truncation of the two ends; the absence of true 
areoles, and the presence of short hairs on the cuticle ; the presence of a trans- 
verse postcloacal cuticular ridge in the male, the posterior edge of which is 
darkest in color, and the absence of a line of hairs around the cloacal aperture. 

Geographical Distribution. Ihave seen specimens from Maryland, Massachu- 
setts, District of Columbia, New York, Maine, Pennsylvania, Montana, and 
Kansas ; and Leidy mentions its occurrence at the Bay of Fundy. The speci- 
mens of “ G. aquaticus” mentioned by Romer (’95), from South America, are 
probably specimens of our subspecies. 


2. G. aquaticus difficilis, n. subsp. 
Figs. 14, 15, Plate 3. 


(Type: 1 male, Leidy coll. 5100, Roan Mt., N. Carolina.) 

Form. General form as in the preceding subspecies, cylindrical with the 
greatest diameter posteriorly, head (Fig. 14) rounded. Posterior end (Fig. 15) 
as in the preceding, but a parabolic line of hairs curves around the cloacal 
aperture, the posterior ends of this line of hairs situated upon the latero-ventral 
surfaces of the tail lobes, at about the plane of anterior bifurcation of the 
latter. 

Cuticle. At the tip of the head there are small, round or polygonal promi- 
nences or areol, of slight elevation, and of a deeper brown color than the sur- 


32 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


rounding portions of the cuticle. These are densely massed together at the 
tip of the head, and a few isolated areole occur along the sides of the body 
near the head. Similar areole, but of larger size, are found also on the dorso- 
lateral surfaces of the tail lobes. The cuticle is elsewhere marked by minute 
intersecting lines, much as in the preceding species ; when studied in alcohol 
the cuticle appears to be areolated in its whole extent, but sections show that 
the apparent areole are nothing but slight elevations between the bundles of 
intersecting lines, the supposed areolz themselves being striated by fine lines, 

Color. Remarkably iridescent. Whole body a light chocolate-brown color, 
the tip of the head the same. There is a dark ring immediately around the 
cloacal aperture. The whole surface of the postcloacal cuticular ridge is of a 
uniform brown color, without darker posterior edge. 

Dimensions. Length, 70 mm.; greatest diameter, .6 mm. 

Comparison. This form resembles, but seems to be distinct from G. aquati- 
cus robustus. It differs from the latter as follows: in the presence of areole 
on the head and tail lobes; in the circumcloacal line of hairs; in the uniform 
dark brown color of the postcloacal cuticular ridge ; in the absence of a 
dark ring around the neck, and of a white tip to the head. These characters 
seem to warrant placing it, preliminarily at least, as a new subspecies. 


3. G. lineatus Leidy. 
Figs. 20-31, Plate 4. 


G. lineatus Leidy, 751. 

G. robustus Leidy, ’56. 

2 G. seta Miill., Diesing, ’61. 

G. lineatus Leidy, Villot, ’74. 
G. aquaticus Linn., Romer, ’96. 


(Types: Leidy coll. 5008, Essex County, New York, 1851.) 

Form. Head end (Figs. 20, 21) rounded, not constricted from the body ; 
body cylindrical, somewhat narrowed anteriorly. Median grooves absent, 
Posterior end (Figs. 22, 28, 28) not swollen, obtusely truncated in the female. 

Males somewhat more slender than the female, and somewhat flattened. 
Tail lobes (Figs. 24-26) rather long and divergent, their distal ends curved 
inwards (ventrad). Cloacal opening elongate, above the lobes, Cuticular 
spicules of an elongate conical form on the median surfaces of the tail lobes, 
though not on the distal ends of the lobes. Two rows of rather long branch- 
ing hairs on the ventral surface of the body; one row on each side of the 
median line, each row extending from a little in front of the cloacal opening to 
a little behind the point of bifurcation of the tail lobes ; the hairs are longest 
in the middle of each line. Tail lobes concave on their medio-ventral surfaces. 

Cuticle (Figs. 29-31). Areolated, areole closely opposed without inter- 
vening spaces ; rectangular or polygonal in outline, frequently elongated in 
the direction of the body axis, and with a tendency to group themselves into 


MONTGOMERY: GORDIACEA. 33 


longitudinal rows which form ridges on the body surface. The areolx vary 
considerably in form and size. 

Color. A pale transparent yellowish white, the female of a deeper buff 
color. In the female the cloacal opening is immediately surrounded by a 
narrow, reddish brown ring. 

Dimensions. Length of largest male, 278 mm. ; greatest diameter, .6 mm. 
Length of largest female, 283 mm. ; greatest diameter, .8mm. The females 
are a little longer and broader than the males, but both sexes are very slender. 

Comparison. This species stands closest to G. violaceus Baird, but differs 
from it in the form of the tail lobes, and in the arrangement of the spicules on 
them, as well as by its very slender form. 

Particular Diagnostic Characters. Very slender and short, of a pale yellowish 
or buff color. Areolz small, close together, with a tendency to form longitu- 
dinal ridges. A line of long hairs to each side of the cloacal aperture in the 
male, and spicules on the tail lobes. 

Geographical Distribution. New York, Maryland, and one specimen secured 
by me in a spring in Chester County, Pennsylvania. Leidy’s type specimens 
were also found in a spring. 


4. G. densareolatus, n. sp. 
Figs. 32-33, Plate 4; Plate 5. 


(Types: Leidy coll. 5063, Fort Bridger, Wyoming.) 

Form of Female. Head end (Figs. 34, 35) conical, terminally rounded, 
the terminal portion slightly constricted off ; mouth opening terminal. An- 
terior portion of the body narrower than the middle and posterior portions. 
With more or less pronounced dorsal and ventral median lines. Posterior end 
(Figs. 38, 39) slightly widened horizontally, obtusely truncated, with a shal- 
low vertical groove on its posterior aspect, in the middle of which the cloacal 
opening lies. 

Form of Male. Generally similar to but more slender than the female. 
The tail lobes (Figs. 36, 37) are short, thick, asymmetrical, and divergent. 
The cloacal aperture is small, circular, and immediately enveloped by a dark 
ring ; it is situated anterior to the tail lobes, on the ventral surface of the body. 
On the antero-ventral surface of the tail lobes is an integumentary (not purely 
cuticular) ridge of slight elevation, the two arms of this ridge converging and 
joining just behind the cloacal aperture. The ventro-median surfaces of the 
tail lobes are concave. From the cloacal aperture, and embracing it, there 
extends cephalad, for a distance about equal to the length of the shorter tail 
lobe, a comparatively wide groove on the ventral surface of the body; at each 
antero-lateral edge of this groove lies a rounded prominence or ridge. The 
ventro-median surfaces of the tail lobes and the postcloacal integumentary 
ridge are covered with short conical cuticular spicules, which extend cephalad 
to each side of the cloacal aperture. 


34 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Cuticle (Figs. 32, 33). Areolated; the areole variable in size and form, 
usually elongate-oval or irregularly pentagonal in outline. Their longitudinal 
axis is usually nearly perpendicular to that of the body, and they tend to pro- 
duce transverse rows or chains, in each of which rows some of the areole are 
confluent. Narrow, shallow grooves separate neighboring parallel rows of 
areole ; and beneath the areole a system of fine intersecting lines is seen.. 
No interareolar bristles or hairs are present. 

Color. In the female (three specimens examined) the extreme tip of the 
head is white, this is followed by a light buff ring, and immediately behind 
the latter a broad transverse reddish brown ring. The cloacal aperture is 
immediately surrounded by a thin black ring, and around the latter is a much 
broader circular area of a reddish brown color. The rest of the body is a deep 
yellowish brown in one specimen; a light chocolate color in the other speci- 
men. Color of the male (a single specimen) similar to that of the female, 
but darker, a deep chocolate color; a nearly black ring surrounds the cloacal 
opening, while the postcloacal integumentary ridge is slightly lighter than the 
surrounding parts. 

Dimensions. Male, length, 290 mm. ; greatest diameter, 1.1mm. Female, 
length of largest specimen, 395 mm. ; greatest diameter, 1.7 mm. 

Comparison. This species is quite similar to the European G. tatrensis 
Janda, but differs from it in that all the areole are of a dark color and 
there are no groups of areoles forming white spots; and in the male the tail 
lobes are shorter and thicker, and there is no “ knorriges, glattes, dreiwandiges 
Hofchen” around the cloacal aperture, such as is described by Janda (93). 
It also differs from G. violaceus Baird in the manner of distribution of the 
spicules on the tail lobes, and in the confluence of the areole. It is however 
most closely allied to G. platycephalus, n. sp. ; these resemblances will be dis- 
cussed under the heading of that species. ; 

Especial Diagnostic Characters. The dense arrangement of the irregular 
areole, which have a tendency to produce transverse rows, and the tendency 
to confluence of the areoles ; the comparatively robust form of the body; the 
short, thick tail lobes in the male, with the conical spines on their ventral sur- 
face, the obscure postcloacal integumentary ridge, and the ventral depression 
within which the cloacal aperture lies. 

Geographical Distribution. The type specimens (2 males, 1 female) are 
from Fort Bridger, Wyoming; and another female from South Montana (coll. 
Acad. Nat. Sci. Philadelphia). 


5. G. platycephalus, n. sp. 
Plate 6; Figs. 46-49, Plate 7. 
(Type of female: coll. Acad. Nat. Sci. Phila., Guatemala. Type of male: 
coll. Acad. Nat. Sci. Phila., South Montana.) 
Form of Female. Anterior portion of the body attenuated and flattened in 
all specimens, and the head constricted from the body. The head (Figs. 42, 6, 


MONTGOMERY: GORDIACEA. 35 


¢, 45) is of slightly greater diameter than the part of the body immediately 
preceding, tip of the head rounded or truncated; in one specimen a groove on 
the ventral surface of the head. Body either flattened or cylindrical, with 
deep dorsal and ventral median grooves. In all females except one the pos- 
terior end (Figs. 42 a, 48, 44) of the body is somewhat constricted for a dis- 
tance of about 6 mm., but the extreme posterior end is usually swollen, some- 
what knob-shaped ; on lateral view this end appears obliquely truncated, the 
posterior end of the body has a vertical groove on its terminal aspect, and the 
cloacal aperture is not exactly terminal, but somewhat ventral. 

In the male the anterior portion (Fig. 40) of the body is not attenuated, 
though it is slightly flattened horizontally; the head is elongate-oval in out- 
line, of greater diameter than the part immediately preceding, and is terminally 
rounded. The body like that of the female, but more slender. Tail lobes 
(Fig. 41) rather slender and long, asymmetrical, their distal ends curved 
ventro-mediad ; they are nearly cylindrical, flattened only on the median sur- 
face. The large, elongate cloacal aperture is situated on the ventral surface of 
the body, and separated from the anterior point of bifurcation of the tail lobes 
by a distance equal to half the length of the tail lobes. This aperture does not 
lie in a groove ; nor do spicules nor long hairs occur near it or on the tail lobes, 
but only minute, short hairs. 

Cuticle (Figs. 46-49). Areolated ; the areole slightly smaller than those 
of G. densarcolatus, more or less of the same size, and either irregularly 
polygonal or somewhat elongate in outline, and then usually elongated in the 
direction of the transverse axis of the body. The areole are usually well 
separated from one another, except in the median line, and show no tendency 
to produce confluent rows. Small interareolar groups of small bristles oecur 
in most of the individuals, these bristles varying in number and form. 

Color. Brown, varying in shade, but never very intense ; tip of head lighter, 
and a more or less pronounced dark ring around the neck. In the male an 
obscure brown ring immediately surrounds the cloacal aperture. 

Dimensions. Length of male, 216 mm.; greatest diameter, 1mm. Length 
of largest female, 335 mm.; greatest diameter, 1.4 mm. 

Comparison. In the configuration of the cuticle this species is most closely 
allied to G. violaceus Baird, and to G. densareolatus mihi. The males of these 
three species are very different, however, in regard to the arrangement of the 
spicules on the posterior end, such spicules being absent in platycephalus. 
This character does not serve to distinguish the females of these species how- 

ever, though the flattening of the anterior portion of the body is diagnostic of 
platycephalus. But I am wholly at a loss to classify one female from Montana 
in the collection of the Acad. Nat. Sci.: it has the flattened head of platyceph- 
alus, with the confluent areole of densareolatus ; its color is a deep buff, with a 
narrow black ring immediately around the mouth, but with no dark ring 
around the neck; the shape of the posterior end and the deep median grooves 
of the body resemble platycephalus, so that on the whole I should be inclined 
to consider it as platycephalus. But might not this specimen be a hybrid be- 


36 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


tween these two species? Though the females of violaceus, densareolatus, and 
platycephalus are so similar, the males are nevertheless very different in regard 
to the form of their posterior ends, so that these species may be regarded as 
genetically related, and we must consider that the course of modification which 
they have undergone has influenced the males more than the females. This 
view of the question cannot be regarded as bizarre, since in other groups of 
animals also the males are in some cases far more dissimilar than the females. 

Especial Diagnostic Characters. The flattening of the anterior end, and the 
constriction of the head from the body ; the slight enlargement of the posterior 
end in the female; the absence of spicules on the tail lobes in the male; the 
presence of small, rounded-polygonal cuticular areoles, which are as a rule well 
separated from one another. 

Geographical Distribution. Guatemala, South Montana, Pennsylvania, 
Bridger Basin, Fort Laramie. 1 male and 7 females examined. 


6. G. platyurus Baird. 
Figs. 50-52, Plate 7. 


G. platyura Baird, ’53. 

G. platyurus Baird, Diesing, ’61. 
G. platyurus Baird, Villot, ’74. 
G. platyurus Baird, Oerley, ’81. 
G. platyurus Baird, Romer, ’96. 


(1 female examined: Leidy coll. 5096.) 

Form. Very massive, flattened dorso-ventrally, with broad dorsal and ven- 
tral grooves, which do not extend quite to the posterior end. Head end (Fig. 
52) conical. Largest diameter posteriorly. The posterior end (Fig. 51) is 
dorso-ventrally flattened, expanded, wider than the preceding portion of the 
body, spatulate in form, with shallow dorsal and ventral depressions. The 
cloacal aperture is terminal. 

Cuticle (Fig. 50). With fine intersecting lines, much as in G. aquaticus 
Linn. Here and there bundles of elevated lines are demarcated from the finer 
lines, and these bundles, which are parallel to the finer lines, deliminate 
rhomboid-shaped spaces. 

Color. A light yellowish buff, somewhat iridescent. Extreme tip of head 
white, behind which is a faint brownish ring. Posterior tip of the body a light 
yellowish white. 

Dimensions. Length, 540 mm.; greatest diameter of body, 2.4 mm. ; great- 
est transverse diameter of tail, 2.3 mm. 

No locality is marked for this specimen ; the only other specimen known, 
the type in the British Museum, is labelled “ Jamaica?” so that it is not yet 
proved that this species is American. It seems to me probable that it does not 
come from the North American continent, since otherwise there would proba- 
bly be numerous examples of this large species extant. Its massive form and 
the spatulate shape of the posterior end are good diagnostic characters. 


MONTGOMERY: GORDIACEA. o7 


7. G. leidyi, n. sp. 
Figs. 53-55, Plate 7; Figs. 56-59, Plate 8. 


(1 female, type: Leidy coll. 5089, no data.) 

Form. Head (Fig. 53) conically pointed, obtusely rounded at the tip, where 
the mouth opening is terminal and forms a slight projection. Body cylindri- 
cal, with deep dorsal and ventral grooves, the ventral one not quite in the 
median plane. Posterior portions of the body for a distance of about 12 mm. 
slightly flattened horizontally, and of slightly less diameter than the middle of 
the body. The dorsal groove of the head extends nearly from the head to the 
posterior end of the body; the ventral groove ends about 5 mm. in front of 
the posterior end. Posterior end (Figs. 56-58) truncated, almost vertically. 
Cloacal aperture (Fig. 57) terminal, nearly in the centre of the disk which 
forms the distal face of the posterior end. This aperture is placed upon a 
round, elevated papilla, the latter sunk in a depression of the distal face of the 
body. To each side of the cloacal papilla is a short vertical, elevated integu- 
mentary ridge, while below the depression in which the cloacal papilla lies is a 
transverse ridge. On the dorsal side of the posterior end (Fig. 56) is a nearly 
U-shaped integumentary fold, to each side of which is an elongated pit or 
depression. The latter pits lie respectively on the dorso-lateral sides of the 
posterior end of the body, and extend posteriorly as far as the vertical tegu- 
mentary ridges which form the lateral boundaries of the depression in which 
the cloacal papilla is situated. The distal end of the dorsal U-shaped fold 
forms a transverse ridge bounding dorsally the depression in which the cloacal 
papilla lies. The dorso-median groove of the body extends on the surface of 
this fold to the posterior end of the latter, the groove being broadest at this 
point. Thus the posterior end of the body is vertically truncated, with a con- 
cave distal face ; in the centre of this depression, situated on the summit of a 
slightly elevated papilla, lies the cloacal aperture ; the outlines of this terminal 
concavity of the body form nearly a square, its boundary being two short 
vertical ridges, a transverse ventral ridge, and a transverse dorsal ridge which 
is the distal end of a U-shaped fold of the integument situated on the dorsal 
side of the end of the body. These relations are somewhat complicated, and 
may be best understood by reference to the Figures 56-58. 

Cuticle. Areolated ; areole (Figs. 54, 55) only slightly elevated, on cross 
section they show no hyaline summit, irregularly polygonal in outline ; they 
are usually elongated in the line of the transverse axis of the body, and show 
a tendency to form short and interrupted rows or chains, contiguous areoles in 
‘such rows being confluent. The areole are separated only by narrow spaces. 
The cuticle is also marked by intersecting elevated lines (Fig. 59) placed at 
considerable but varying distances apart, these lines being easily visible on the 
alcoholic specimen. Interareolar bristles are absent. 

Color. Head end light yellowish brown, the rest of the body a deep yellow- 
ish brown color, with an obscure dusky brown ring on the head. In the 

VOL. XXXII. — No. 3. 2 


38 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


median line of the dorsal groove of the body are two narrow, parallel stripes 
of an intense reddish brown color, which are in contact with one another in 
the median line. In the ventral median groove of the body are two parallel 
stripes of about the same color as those in the dorsal groove, but with this 
difference, that they are separated from one another by a distance about equal 
to the diameter of either of the lines, and that the two ventral stripes are of 
not quite the same diameter. Both the dorsal and ventral stripes of color 
disappear near the two ends of the body. 

Dimensions. Length, 295 mm.; greatest diameter, 1.5 mm. 

This species is sharply distinguished from all other species of the genus 
known to me by the peculiar form of the posterior end, and by the colored 
stripes lying within the median grooves of the body. Unfortunately the 
locality is not given for the specimen. I have named it in honor of the pioneer 
student of the American Gordiacea, Joseph Leidy. 


3. G. agassizi, n. sp. 
Figs. 63-66, Plate 9. 


(Type, 1 male: Harvard collection no. 296, Sandwich Isl.) 

Form. Body much flattened dorso-ventrally, without well marked median 
grooves; the body is flattened in such a way that the dorsal side is rounded, 
the ventral side concave, so that a cross section would show the body to be 
somewhat sickle-shaped. Head end likewise dorso-ventrally flattened. The 
particular characteristic of this species, however, is that the broad plane of the 
neck does not coincide with the broad plane of the head, but is nearly vertical 
to it (Fig.63). Thus the flattening of the head and of the body lies in approx- 
imately the same plane, while the neck region (for a distance of about .9 mm.) 
is twisted around through an angle of nearly 180 degrees, and hence the broad 
plane of the neck is nearly vertical to that of the head and to that of the body. 
Hence in viewing the head end either from the dorsal (Fig. 63) or the ventral 
aspect, the neck appears like a short slender thread. This relation has prob- 
_ ably been produced by a torsion of the neck region through an angle of nearly 
180 degrees. The outline of the head, viewed from the flattened surface, has 
somewhat the shape of an unbarbed arrow-head, broadest posteriorly and with 
rounded tip ; the mouth opening is large, transversely elongated, and situated 
at the termino-ventral margin of the head. The neck inserts itself along an 
elevated ridge which circumscribes the posterior portion of the head. On the 
dorsal surface of the head (Fig. 63), to each side of the median line, are found 
just behind this elevated ridge a number of small ridges which are parallel to 
one another (i. e. those on the same side of the ridge are parallel), and these 
are obliquely disposed to the large ridge. These relations are difficult to 
describe, but may be understood by comparing the figure. 

The tail lobes (Figs. 65, 66) are bent ventrad, nearly at right angles to the 
posterior end of the body region proper. Each tail lobe is much flattened 
laterally, and is very short; it is somewhat rounded on the lateral, and corre- 


oO 


MONTGOMERY: GORDIACEA. 39 


spondingly concave on the median side. Viewed from the side (Fig. 65) 
each shows a more or less conical outline, broadest at the proximal end, 
rounded at the distal end. The dorso-median margin is slightly thickened. 
The flattened planes of the two lobes are not parallel, their dorso-median 
margins being much closer together than the ventro-median; the proximal ends 
of their dorso-median margins are in contact, while the ventro-median margins 
are farthest apart proximately (Fig. 66). The median plane between the 
two lobes is vertical to the flattened plane of the posterior end of the body 
proper. The tail lobes may well be termed leaf-shaped. 

Cuticle (examined in alcohol only, since it seemed inadvisable to section the 
single specimen at hand). The surface (Fig. 64) viewed with low powers 
of the microscope, shows very plainly a system of deep intersecting lines, be- 
tween which lie slightly elevated areole of rhombic or rhomboid outline. 
There are necessarily two systems of parallel lines; and in one of these two 
systems the lines tend to occur in pairs. 

Color. The body is a uniform rufous-brown color, the tail lobes somewhat 
lighter. The mouth region of the head is yellowish, behind which follows a 
zone of a nearly black color; the posterior portion of the head is but little 
darker in color than the body. 

Dimensions. Length, 158 mm.; greatest diameter of head, 1 mm.; greatest 
diameter of body, 1.5 mm. 

Comparison. This species may be very sharply distinguished from any 
other Gordiacean yet described, by the torsion of the neck through an angle of 
nearly half a circle, and by the extreme flattening of the tail lobes. It is the 
only species known from the Sandwich Islands. 


9. G. capitosulcatus, n. sp. 
Figs. 67-69, Plate 9; Fig. 70, Plate 10. 


(Type, 1 male: Harvard coll. 1466 a, Cuba.) 

Form. The body is dorso-ventrally slightly flattened, with slight dorsal 
and ventral median grooves. The head (Figs. 67, 69) is flattened laterally, 
higher than broad, and is separated from the body by a slight constriction 
(neck). The head has the greatest diameter at the anterior end, where it is 
obliquely truncated, the dorsal margin projecting slightly farther forwards 
than the ventral. The terminal aspect (Fig. 67) of the head is concave, the 
large mouth opening situated in the median line, nearer the ventral than the 
dorsal margin of the head. At each anterior dorso-lateral margin of the head 
is a ring-shaped prominence (Fig. 69), which surrounds a pit-like depression. 
It would be impossible to determine the structural significance of these pits 
without sectioning the head, but this was not permitted on the single speci- 
men examined. 

The tail lobes (Fig. 70) are slightly divergent; each is terminally rounded, 
nearly cylindrical on cross section, but concave on the median surface. The 
lobes are long and slender, and apparently bear no hairs or spicules. The 


40 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


cloacal aperture is situated on the ventral surface of the body, a short distance 
in front of the point of union of the two lobes. 

Cuticle (Fig. 68). With small elevated areoles, situated close together. 
The areoles are somewhat variable in size and form, but are mostly rounded- 
polygonal in outline. Their surface is not smooth, as in the other species of 
the genus examined by me, but with irregular short tubercles. Interareolar 
bristles are apparently absent. 

Color. Pitch-black to the naked eye, but with a brownish tinge when 
viewed with the microscope. The margins of the ring-shaped prominences of 
the head are of a whitish color. 

Dimensions. Length, 165 mm.; greatest diameter, 9 mm. 

Especial Diagnostic Characters. The presence of depressions on the anterior 
dorso-lateral margins of the head ; the roughened surface of the areoles; the 
intense black color. 

Comparison. This form differs from G. violaceus, densareolatus, and platy- 
cephalus by the roughened surface of the areoles, the coloration, and the 
presence of the pits on the head. It has no close resemblance to any of the 
species described by Camerano from South America, and on the whole appears 
to be a well defined species. 


10. G. paranensis Camer. 
Figs. 71-74, Plate 10. 


G. paranensis Camerano, 722, ’94. 
G. paranensis Camer., Romer, 96. 


(1 female, 5 males: Harvard coll. no. 1478, Casabianca, Chile.) 

Form of Female. Body somewhat flattened dorso-ventrally, without well 
marked median grooves. Head conical, concave on the terminal aspect, 
mouth terminal ; head not constricted from the body. Posterior end (Fig. 71) 
truncated, with a circular depression on its terminal aspect, in which the 
cloacal opening lies ; this posterior end of the body is round on cross section, 
while the immediately preceding portion of the body is much flattened dorso- 
ventrally. 

Form of Male. Body more slender than in the female, and with more or 
Jess well marked median grooves. In one male (Fig. 74) the head end is 
conical with rounded tip; in the others it is separated from the body by a 
slight constriction, and is terminally truncated, the terminal face concave 
(Fig. 73) ; on this terminal aspect of the head in one specimen is a vertical, 
median ridge, to each side of which is a depression. A conical and a truncate 
form of head being found in different specimens of this species would lead to 
the conclusion that the truncate form, in which the anterior aspect of the head 
is concave, is probably due to a muscular contraction of the tip of the head. 
The tail lobes (Fig. 72, a, b) are comparatively short and thick, flattened on 
their proximo-median surfaces as well as on their dorso-lateral surfaces. 


MONTGOMERY: GORDIACEA. 41 


Apparently neither hairs nor spicules occur in the vicinity of the lobes. At 
the anterior point of union of the tail lobes, on the ventral surface of the body, 
is situated a V-shaped ridge, each arm of which is placed on the ventro-median 
margin of the corresponding tail lobe, the two arms of the V converging, and 
joining at an angle cephalad at the anterior point of union of the tail lobes. 
Anterior to this ridge is situated a broad and deep depression. At the deepest 
part of this depression, i. e. in the medio-ventral line just anterior to the ridge 
described, is situated the cloacal aperture; this aperture lies on the summit of 
a slightly elevated papilla. The anterior margin of the depression which sur- 
rounds the cloacal papilla forms a sharp ledge, irregularly semicircular in out- 
line (the opening of the semicircle directed caudad); this sharp ledge, forming 
the anterior and lateral margin of the cloacal depression, is not elevated above 
the level of that portion of the ventral surface of the body which lies anterior 
to the depression. Along this ledge are arranged a row of short, thick hairs. 
Accordingly, we find on the ventral surface of the posterior end of the male a 
narrow V-shaped ridge at the base of the tail lobes; anterior to this a large and 
deep depression, in the centre of the posterior part of which the cloacal papilla 
is situated; and the anterior and lateral boundary of this depression, formed by 
a nearly semicircular sharp ledge. 

Cuticle. There are no areoles, but a system of broad intersecting, oblique 
lines, between which are much finer intersecting lines. Short hairs also occur 
here and there, but sparsely. The cuticle is thus very similar to that of G. 
aquaticus robustus (Leidy). 

Color. Body of a dull olive-brown color. Tip of the head yellowish white, 
the remainder of the head reddish brown, varying in shade. The posterior end 
of the female is yellowish ; the pit in which the cloacal aperture lies is of a 
deep reddish brown color, there being thus a disk of this color immediately 
around the aperture. Inthe male the postcloacal cuticular ridge is reddish 
brown, its posterior edge black. 

Dimensions. Length of female, 470 mm.; greatest diameter, 1.8 mm. 
Length of largest male, 340 mm. ; greatest diameter, 1.3 mm. 

Especial Diagnostic Characters. The presence of a postcloacal ridge in the 
male, and the presence of a sharp precloacal ledge which bounds the cloacal 
depression; the intersecting lines of the cuticle. 

Comparison. These specimens seem to agree wholly with Camerano’s 
description of the species. This form is most closely allied to G. aquaticus 
robustus (Leidy). 

Geographical Distribution. Asuncion, Paraguay; Palmeira (Parana); Casa- 
bianca, Chile. 


42 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


11. G. violaceus Baird. 
Figs. 60-62, Plate 8; Figs. 75-77, Plate 11. 


G. violaceus Baird, ’53. (For the synonymy of descriptions of specimens from 
other localities than America, cf. Romer, 796.) 

@ G. reticulatus Villot, ’74 (from California). 

2 G. violaceus Baird, Villot, ’87. 

2 G. violaceus Baird, Romer, ’95 (from Arizona). 

2 G. violaceus Baird, Romer, ’96. 


(1 female, Harvard coll. no. 1465, California ; 1 female, Harvard coll. no. 
1666 c, Cuba.) 

Description of the Californian Specimen. Body cylindrical without median 
lines. Posterior and especially the anterior portions of the body somewhat 
narrower than the middle; head (Fig. 61) of a rounded conical form, not con- 
stricted from the body, mouth terminal. Posterior end (Fig. 60) of the same 
diameter as the immediately preceding portion of the body, obtusely rounded 
terminally; the small, round cloacal aperture is terminal, Cuticle (Fig. 62) 
areolated: the brownish areole vary somewhat in size, are irregularly polyg- 
onal, and do not form rows but are well separated from one another; a few 
small interareolar bristles are present. Color: a clear chocolate-brown, head 
paler, a deep reddish brown ring around the mouth. Length, 130 mm. ; great- 
est diameter, 9 min. 

Description of the Cuban Specimen. Body nearly cyclindrical, with dorsal 
and ventral median grooves. Head cyclindrical, narrower than the portion of 
the body immediately preceding, terminally truncated (Fig. 76) ; this plane of 
truncation is slightly convex, the mouth situated in its centre. The anterior 
portion of the body is gradually attenuated, of less diameter than the middle 
portion. Posterior end of the body (Fig. 75) obliquely truncated, in that the 
dorsal margin projects farther caudad than does the ventral margin ; the pos- 
terior end of the body is flattened on its ventral surface. In the medio-ventral 
line is a shallow narrow groove, which passes dorsad on the terminal aspect of 
the body, this groove being deepest at the dorso-terminal margin of the body. 
Within this groove lies the terminal cloacal aperture. Cuticle (Fig. 77) 
areolated ; areole low, irregularly rounded in outline, smooth superficially, 
close together; the areolz are very little darker than the inter-areolar spaces ; 
between them lie thick, conical hairs, which are higher than the areole. 
Color a uniform grayish brown, head lighter; the mouth is surrounded by a 
narrow reddish brown ring, and the vertical groove at the posterior end of the 
body is also of this color. Length, 112 mm.; greatest diameter, 1 mm. 

Comparison. There is some doubt in my mind whether these specimens 
should be attributed to @. violaceus Baird, but they certainly come closer to this 
species than to any other, and until further specimens are examined from these 
localities may best be placed under this species. But we know that platy- 
cephalus and densareolatus come very close to violaceus in the structure of the 


— 


MONTGOMERY: GORDIACEA. 43 


cuticle, but differ markedly in the form and armature of the posterior end of 
the male; and so it may be that the males of these two specimens, when dis- 
covered, may also be found to differ from the males of violaceus. But it would 
be inadvisable to classify these two females as a new species until the males 
are known. 

The Californian form agrees very closely with the G. reticulatus of Villot 
(74), also from California, but the male of the latter is likewise unknown, so 
that reticulatus must still be regarded as a doubtful species. Villot (’87) and 
Romer (’95, ’96) hold the view that reticulatus may be synonymous with viola- 
ceus. The males of specimens from all these localities must first be examined 
before we can decide whether the true violaceus really occurs in America, or 
whether a subspecies or different species, distinct also from platycephalus and 
densarcolatus does not take its place. Hence these two doubtful female 
specimens from Cuba and California, may only preliminarily be placed under 
violaceus. 


PARAGORDIUS, n. gen. (cf. the Appendix). 


. (Type of the genus: Gordius varius Leidy, ’51, ’56.) 

Generic Characters. The cloaca in the adult female is remarkably long 
(Fig. 86), nearly half an inch in length, and the caudal ganglion (Fig. 
79, N. Gl.) is in direct connection with the cloacal epithelium, and at no 
point with the epidermis. The male is characterized by the absence of a 
eloacal musculature (Fig. 78). The trilobation of the posterior end of the 
female (Figs. 88-90) possibly also furnishes a true generic character. 

Thus Paragordius differs anatomically more widely from Gordius and Chor- 
dodes, than the last two do from each other; for in both of the last two the 
female cloaca is very short, usually a fraction of a millimeter, and the caudal 
ganglion is never in contact with the cloacal epithelium, and in these also 
the male always possesses a cloacal musculature (Fig. 18). I am inclined to 
suppose that the European Gordius tricuspidatus (Dufour) (G. gratianopolensis 
Dies.) should be placed in this new genus, since its female has also a triloba- 
tion of the posterior end. But unless the latter species be found to show also 
the anatomical generic characters given above, it must be kept separate from 
Paragordius, since it is doubtful whether the mere trilobation of the posterior 
end constitutes a good generic character, for we find in the female of G. tolo- 
sanus Duj. a tendency to bilobation of the posterior end of the body. I have 
had no opportunity to examine @. tricuspidatus, and find no description of the 
anatomical structures at issue, so that the generic position of this European 
species must still remain doubtful, though it certainly should not be placed 
under Chordodes, as Romer (’96) has done, since the male has the typical bilo- 
bation of the posterior end shown by all true Gordii. I quite agree with 
Janda (93) that the shallow ventral groove on the posterior end of the males 
of Chordodes is one of the important characters of the genus, since I have found 
this typical form of the posterior end in all male Chordodes examined by me, 


44 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


and it has been found characteristic for all the males of Chordodes which have 
been heretofore described. The characters of these three genera of Gordiacea 
may be compared as follows. 

Gordius. Posterior end of the male bilobed, a cloacal musculature present; 
posterior end of the female rarely much swollen, never cleft (except in G. tolo- 
sanus, where it is deeply grooved rather than cleft); the caudal ganglion in the 
female not in contact with the cloacal epithelium, the cloaca very short; cu- 
ticula marked with intersecting lines or with low areolz, never with high tuber- 
cles or papille, though frequently with short hairs or conical processes (spicules). 

Chordodes. Posterior end of the male not bilobed, but only with a compara- 
tively shallow groove on the ventral surface; posterior end of the female usu- ~ 
ally swollen, never cleft ; the caudal ganglion in the female not in contact with 
the cloacal epithelium, the cloaca very short; the male with a special cloacal 
musculature; cuticle usually marked with high tubercles or papille, and 
apparently always with hyaline club-shaped processes, which are very differ- 
ent from the interareolar hairs of Gordius. 

Paragordius.. Posterior end of the male bilobed, no cloacal musculature ; 
posterior end of the female trilobed ; the caudal ganglion in the female is in 
contact with the cloacal epithelium, and the cloaca is long; cuticle as in Gor- 
dius, except that the papille are enveloped in a hyaline layer, which forms the 
external layer of the cuticle (Fig. 91, a). 

These three genera appear to be very natural groups, and each is to be dis- 
tinguished by the union of certain characters, rather than by the presence of 
any single character. Of the three, Gordius occupies an intermediate position, 
with relations on the one hand to Chordodes, on the other to Paragordius, 
though it shows the greater affinity to Chordodes ; while there are no good 
characters in common between Chordodes and Paragordius. Thus Gordius 
might be regarded as the more primitive parent form, from which the others 
have differentiated ; but I reserve a discussion of this point for a subsequent 
contribution. 

The following preliminary note on the caudal ganglion of Paragordius (in 
the female) may be of anatomical interest. This ganglion lies in contact with 
the cloacal epithelium at the anterior point of bifurcation of the two lateral 
tail lobes (Fig. 79). The posterior margin of this ganglion forms a thin verti- 
cal lamina, which may be in contact with that portion of the epidermis lying 
between the two lateral lobes, but it certainly does not terminate in contact 
with the epidermis of the ventral surface of the body. The ventral nerve 
chord anterior to the caudal ganglion lies in the ventro-median line between the 
intestine and the longitudinal musculature of the body wall, as in both Gordius 
and Chordodes, as far as the latter genera have been examined. But there are 
certain small nerves which take their origin from the antero-dorsal margin of the 
caudal ganglion, and these nerves lie directly beneath the cloacal epithelium. 
These relations were studied on sections of two females; and anterior and pos- 
terior nerves may be distinguished with reference to the course which they pur- 
sue. The anterior neryes, which are of greater diameter than the posterior 


MONTGOMERY: GORDIACEA. 45 


ones, varied in number in the two specimens sectioned. In the one, two 
nerves arise from the dorso-lateral margin of the ganglion, and may be traced 
cephalad for a number of sections ; they diverge only slightly; in the other 
specimen there is, in addition to the two lateral anterior nerves, also an un- 
paired median nerve of greater diameter than the other two, which bifurcates 
at its anterior end. The posterior nerves arise a couple of sections behind the 
anterior ones, and are two in number (one on each side of the median line), 
though in one of the specimens there appeared to be two on one side and one 
on the other; these posterior nerves pass caudad, diverging in their course, and 
may be traced into the lateral tail lobes, where they divide into still smaller 
nerves. 

In one male sectioned an elongated cuticular penis was present in the cloaca, 
this being only the second case of a penis being observed in a Gordiid, the other 
case having been observed by Vejdovsky. But the description of these inter- 
esting anatomical details must be postponed to a later paper. 


12. Paragordius varius (Leidy). 
Figs. 78-85, Plate 11; Figs. 86-93, Plate 12. 


Gordius varius Leidy, ’51, 756, 758. 

G. varius Leidy, Diesing, 1861. 

G. gratianopolensis Charvet, Schneider, ’66. 
G. varius Leidy, Villot, ’74. 

G. trilobus Villot, Oerley, ’81. 

G. varius Leidy, Camerano, ’93. 
Chordodes varius Leidy, Romer, ’96. 


(Leidy’s original type specimens have apparently not been preserved.) 

Form of the Female. The anterior and posterior portions of the body are 
narrower than the middle, the decrease in diameter being very gradual; the 
anterior is narrower than the posterior end. The head end (Figs. 83-85) is 
obliquely truncated in such a way that the antero-ventral margin projects 
farther forward than does the antero-dorsal; this truncated plane, which 
forms the terminal aspect of the head, is very nearly flat. The mouth lies 
near the ventral edge of the truncated plane. The posterior end (Figs. 88-90) 
is trilobed, there being one dorso-median and two latero-ventral lobes; these 
lobes have no cuticular spines on their surface, and in the great majority of the 
numerous specimens examined are of equal length. Two specimens in the 
Harvard collection were exceptions to this equality in length : in one the dorsal 
lobe was slightly longer than the others, in the other slightly shorter. But the 
dorsal lobe is narrower than the others, and further differs from the latter in 
having an elevated median ridge on its ventral surface, so that on cross section 
it appears triradiate (Figs. 80, 81). The lateral lobes are crescent-shaped on 
cross section. The cloacal aperture, wholly hidden by these lobes, lies at their 
base and between them, so that the cuticle and epidermis of the inner surface 
of the lobes are directly continuous with the cuticle and epithelium of the 


46 BULLETIN :. MUSEUM OF COMPARATIVE ZOOLOGY. 


cloaca (Fig. 86). The lobes may be either parallel or divergent, and hence 
are probably movable. 

Form of the Male. The anterior end (Fig. 82) as in the female, but the 
body more slender. The tail lobes (Fig. 87) are comparatively long and 
slender, cylindrical in shape, and obtusely rounded terminally. Small conical 
spicules occur on the medio-ventral surfaces of the anterior half of the lobes, 
and short hairs on their anterior surfaces. The elongate cloacal aperture lies in 
the medio-ventral line of the body, anterior to the tail lobes. 

Cuticle. On cross section (Fig. 91, a) an outer thin hyaline layer is seen, and 
an inner, much thicker fibrous layer. Embedded in the hyaline layer are small 
lozenge-shaped bodies, which stain more deeply than any other portion of the 
cuticle, and which correspond to the areole seen on surface views. The exter- 
nal surface of the hyaline layer of the cuticle is marked by short conoidal 
processes of the same structure as the hyaline matrix; these are not seen on 
surface views. On surface view (Figs. 91,b-93) the cuticle appears areolated: 
the areole are small, variable in size and form, and irregularly arranged. 
Sometimes they occur in groups, sometimes in interrupted longitudinal rows ; 
their arrangement varies both in different individuals as well as on different 
portions of the same individual. The areoles are irregularly polygonal in 
outline. In one female larger brown-colored areoles were present in addition 
to the smaller, lightly colored ones; the former were mainly arranged in the 
form of longitudinal ridges, and were irregularly star-shaped in outline. 

Color. Color usually lighter in the females than in the males, varying from 
a light brown or yellowish to a dark brown (the larger individuals usually 
darker). The tip of the head is white or a pale brownish; just behind there 
is a dark ring of color, usually rusty brown or even black, rarely pale ; this 
ring is darkest at its anterior edge, and darker on the dorsal than on the ven- 
tral side of the body. At least a trace of this ring is to be seen on all speci- 
mens when mature, though the intensity of its coloration is very variable. 

Dimensions. Length of largest male seen, 350 mm.; greatest diameter, .9 mm. 
Length of largest female, 290 mm. ; greatest diameter (of a flattened individual), 
2mm. The males are more slender and average considerably shorter than 
the females. 

Especial Diagnostic Characters. The trilobation of the posterior end of the 
female, the long and cylindrical tail lobes of the male, the oblique truncation 
of the head end, and the usually very dark colored ring around the head, 
render this species very easy of identification. 

Comparisons. This species has the greatest affinity to Gordius (Para- 
gordius ?) tricuspidatus (Dufour); but it differs from it in that there are no 
spicules or spines upon the tail lobes of the female, and in that the dorsal is 
narrower than the lateral lobes; further, in varius the areoles of the cuticle 
are frequently arranged into rows or groups. 

Geographical Distribution. I have examined specimens from the following 
localities: New York, Maine, Massachusetts, New Jersey, Pennsylvania, Vir- 
ginia, Kansas, California, and Guatemala; and it has been observed by others 


MONTGOMERY: GORDIACEA. 47 


in Mexico, Peru, and Bolivia. It appears to have a very extensive range, and 
it and G. aquaticus robustus are the most abundant forms in the northeastern 
portion of the United States. 


Genus CHORDODES (Creplin) Mobius. 


13, C. morgani, n. sp. 
Fig. 94, Plate 12; Figs. 95-100, Plate 13. 


(1 female, type, in my possession, from Maryland; a second female from 
Iowa in the Harvard coll. no. 1470.) 

Description of the Type Specimen. Form: Perfectly cylindrical without 
median lines, Anterior end gradually attenuated, head (Fig. 98) much nar- 
rower than the posterior end, rounded. Tail end (Fig. 97) swollen, obtuse 
posteriorly, the swelling most pronounced on the ventral aspect. Cuticle: 
With three kinds of prominences (Figs. 99, 100): (1) Larger tubercles which 
are about twice as high as broad, nearly circular on cross section, and rounded 
apically; these bear no hairs, and are distributed at nearly equal distances on 
the surface of the cuticle, with only a slight tendency to arrange themselves 
into disjointed groups. (2) Smaller tubercles, which are pointed at the apex 
and more or less conical in form; these vary considerably in height, but are 
never more than a quarter the height of the preceding kind. Each bears on its 
summit a single delicate hair. These tubercles are arranged quite densely on 
the surface of the cuticle, and the larger ones among them are grouped closely 
around the tubercles of the Ist order; in the median line of the body they are 
more numerous, especially the larger ones of them, which form groups be- 
tween as well as around the tubercles of the 1st order. (3) Delicate slender 
hyaline processes, frequently club-shaped, which occur only sparsely, and are a 
little higher than the first kind of tubercles. Color: A uniform yellowish 
brown. Dimensions: length, 222 mm. ; greatest diameter of body, 1.1 mm. 

Description of the Second Specimen. Form: Anterior end pointed, and head 
tip (Fig. 94) rounded as in the preceding, but on the ventral surface of the 
head, to each side of the median line, is a short longitudinal groove. Body 
nearly cylindrical, with narrow but deep median grooves; on a portion of 
the surface there are likewise irregular longitudinal grooves. Posterior end 
(Figs. 95, 96) swollen, though of less diameter than the body at its middle 
point; this distal swelling is of greater diameter than the dorso-ventrally 
flattened portion of the body which immediately precedes it. The posterior 
end is truncated terminally, and near the centre of this terminal aspect 
(Fig. 96) is situated the cloacal aperture at the middle point of a vertical 
ridge, to each side of which is a groove. On the dorso-lateral sides of the 
posterior end larger and deeper grooves are situated. Color; A uniform dull 
chocolate-brown, the terminal aspect of the head somewhat lighter in color. 


48 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Cuticle: as in the preceding specimen. Dimensions: length, 158 mm. ; 
greatest diameter of body, 9 mm. 

Especial Diagnostic Characters. The peculiarities of the cuticular tubercles, 
and the uniform coloration. 

Comparisons. The papille of the cuticle have some resemblance to those of 
C. hamatus Romer, from West Africa. But the arrangement and form of the 
papille of the latter form is not quite the same, judging from Romer’s (’96) 
description of them: “Die Haut ist mit Papillen bedeckt von der Form 
kleiner Hiigel und spitzer Zacken. Sie sind ganz niedrig; ihre Form ist 
nicht gleichmissig, auch ihre Entfernung von einander nicht die gleiche, aber 
sie haben im allgemeinen denselben Habitus. . . . Kopfende des Weibchens 
stark zugespitzt.” 

Thus far only two specimens observed, from Iowa and Maryland, respectively. 

I have the pleasure of naming this species in honor of my friend Dr. Thos, 
H. Morgan, of Bryn Mawr College, who kindly gave me the first specimen 
seen. 


14. C. puerilis, n. sp. 
Figs. 101-105, b, Plate 13. 


(Type, 1 male: Leidy coll. no. 5071, from a cockroach. A second male se- 
cured by me in Chester County, Pennsylvania.) 

Form. Anterior portion of the body more slender than the posterior. 
Head end (Figs. 101, 102) dorso-ventrally flattened, obliquely truncated ter- 
minally, mouth opening terminal. Middle and posterior portions of the 
body horizontally flattened in the larger specimen, cylindrical in the smaller. 
Posterior end of the body (Fig. 103) narrower than the preceding part, almost 
cylindrical, terminally rounded; a median groove is present on its ventro- 
terminal end, and to each side of this groove the integument forms a slightly 
elevated ridge. 

Cuticle. With four kinds of prominences (Fig. 105, 6): (1) the largest tuber- 
eles, usually of a rounded-conical shape, but vary somewhat in length (the 
length is usually one third greater than the largest diameter, which is at the 
base). On the rounded apex occur short, rather thick hairs, terminally 
pointed, from 5 to 10 hairs to each tubercle. (2) Long hyaline, slender pro- 
cesses, which vary considerably in form, but are usually either finger-shaped or 
club-shaped ; these are the highest and least abundant of all cuticular promi- 
nences, and are devoid of hairs. (3) These most abundant tubercles are usu- 
ally conical in shape, and from one fourth to one half the length of the first 
kind; each bears on its summit a single strong hair, which is slightly longer 
than the hairs of the 1st kind of tubercles. (4) The smallest tubercles are not 
quite as high as the preceding kind, are hemispherical, and without hairs. On 
surface views of the cuticle (Figs. 104, 105, a) the various kind of tubercles are 
seen to be closely arranged together, without any regular distribution into 
groups. All these tubercles are very small, and may be distinguished clearly 
only on thin sections studied with the ;, immersion lens of Zeiss. 


MONTGOMERY: GORDIACEA. 49 


Color. A more or less deep chocolate-brown, somewhat lighter on the 
anterior end; head (not merely its terminal tip) almost white. 

Dimensions. Length of the larger individual, 212 mm. ; greatest diameter of 
body, 1 mm. 

Especial Diagnostic Characters. The three kinds of minute papillz, which 
are not arranged into particular groups, furnish the chief diagnostic character. 

Comparisons. This species differs in the characters of its cuticle from all 
foreign species of the genus. These characters appear to resemble those de- 
scribed by Camerano (’97, b) for C. talensis ; but the description of this author 
is difficult to understand, and is without figures, so that it seems justifiable to 
class our species as new, at least until further descriptions and figures of 
talensis are published. j 


15. C. gordioides, n. sp. 
Figs. 106, 107, Plate 13; Figs. 108-110, Plate 14. 


(Types, males and 1 female: coll. Acad. Nat. Sci. Phila., Hayden’s Survey, 
S. Montana.) 

Form of Male. Anterior end slender, cylindrical, attenuated, head (Fig. 108) 
somewhat conical with obtusely truncated tip; mouth terminal. Body for 
the most part cylindrical, without well marked median grooves; thickest in 
the posterior fourth. Posterior end, for the distance of 10 mm., consider- 
ably narrower than the immediately preceding portion, and slightly flat- 
tened dorso-ventrally. Cloacal aperture on the ventral surface (Fig. 110), 
anterior to the posterior tip of the body; just anterior to this aperture is a 
slightly elevated semilunar ridge. In the medio-ventral line of the body, 
behind the cloacal aperture, is a shallow groove, to each side of which is a 
longitudinal prominence. The posterior end of the body is rounded termi- 
nally. 

Form of Female. General form as in the male, the body thickest in the mid- 
dle, narrowed anteriorly, more or less flattened posteriorly. Posterior end 
(Fig. 109, a, b) enlarged, somewhat spherical, constricted off from the imme- 
diately preceding portion of the body; cloacal aperture terminal, nearer the 
dorsal than the ventral side. 

Cuticle. With low flattened tubercles, but little higher than the areole of 
Gordius densareolatus. On surface views (Fig. 107) these appear small, ovoid 
or rounded-polygonal in outline, but they vary considerably in shape and some- 
what in size, and are often much elongated. They have a tendency to arrange 
themselves into parallel rows, contiguous rows being well separated from one 
another ; the direction of these rows is slightly oblique to the transverse axis of 
the body, and their component tubercles are more or less confluent. Light 
colored lines also are seen on the surface of the cuticle, the distances which sepa- 
rate these lines being variable ; these lines, the optical representations of shallow 
grooves, demarcate rhomb-shaped portions of the cuticle. On cross sections 
(Fig. 106) the tubercles are seen to be low, and usually flattened apically, with 


50 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


rounded margins ; occurring at intervals, but sparsely, are club-shaped slender 
hyaline processes such as are characteristic of the genus, and these are about 
double the height of the tubercles ; and also small inter-tubercular groups of 
short, spiniform hairs. 

Color. Inthe males the head is yellowish white, with a narrow black ring (ap- 
pearing like a spot) immediately around the mouth; the rest of the body a deep 
chocolate-color, or rufous-brown, with evidences of lighter brown bands and 
spots on the posterior end, though these spots were absent in one individual; 
in the smallest male the body color was a clear yellowish brown. In the 
single female specimen a black ring immediately surrounded the mouth open- 
ing; but the rest of the body is a clear yellow, the head and posterior tip of 
the body somewhat lighter. 

Dimensions. Length of largest male, 215 mm.; greatest diameter, 1.38 mm. 
Length of female, 150 mm.; greatest diameter, .8 mm. 

Diagnostic Characters. The presence of flattened tubercles, resembling the 
cuticular areoles of the genus Gordius, none of which have a light spot on the 
surface, and which tend to arrange themselves into irregular oblique rows, and 
the presence of inter-tubercular groups of small] hairs, serve to distinguish this 
species. 

Comparisons. This species resembles most closely C. occidentalis, n. sp. 
(q. v.). It also bears some resemblance to C. moluccanus Romer (’96), but 
differs from the latter in the form and more especially the arrangement of 
the tubercles of the cuticle, and in the swelling of the posterior end of the 
female. 

The cuticle of this species resembles that of a Gordius rather than that of a 
Chordodes, except that it shaws the typical hyaline processes of the latter 
genus ; and since its cuticle thus unites characters of these two genera, the 
specific name gordioides is suggested. 


16. C. occidentalis, n. sp. 
Figs. 111-114, Plate 14; Figs. 115-117, Plate 15. 


(Type 1 male: Harvard coll. no. 1469, San Francisco, Cal. A second male: 
Harvard coll. no. 1481, Rio Gila, Arizona.) 

Form. Whole body much flattened dorso-ventrally, with the exception of 
the posterior end, in the type without, in the second specimen with, shallow 
median grooves ; anterior and posterior ends narrower than the middle portion 
of the body, though the anterior end is attenuated only for a distance of about 
lem. Head (Figs. 111, a, b) flattened, conical, the tip rounded or else obtusely 
truncated, and then the dorsal margin projects farther forward than does the 
ventral. Mouth terminal. In the second specimen (Figs. 114, a, b) a Y-shaped 
ridge is situated on the terminal aspect of the head, the mouth placed at the 
point of union of the three arms of the Y; the unpaired arm of this Y-shaped 
ridge runs from the mouth mediad and dorsal, the paired arms latero-ventrad, 


eg ow oper 


MONTGOMERY: GORDIACEA. 51 


Posterior end of the body is nearly cylindrical, somewhat flattened ventrally, 
and terminally either rounded or obliquely truncated. On the medio-ventral 
surface of the posterior end (Figs. 112, 113, a, 6) is a shallow groove, which 
extends from the cloacal aperture caudad to the distal end of the body, and to 
each side of this groove is a longitudinal ridge of slight elevation. 

Cuticle. On surface view (in Canada balsam) two kinds of low, flattened 
tubercles or areoles are to be seen (Figs. 115, 117): (1) The larger (those of 
greater diameter) are darker in color, and either elongate (in one specimen) or 
rounded-polygonal in outline. In the median line of the body they are smaller 
and more densely arranged than elsewhere. In one specimen (the type, Fig. 
115) these areoles were non-confluent ; but in the other they show a tendency 
to group themselves in interrupted, transverse rows, and consequently are 
more elongate in form than in the former (type) specimen. On the surface of 
some of the larger areoles is seen a small, circular clear spot, in the centre of 
which appears a small granule; sections show that this spot is a pit on the 
surface of the tubercle, which is nearly filled with a small rounded-conical 
process ; those tubercles on the lateral surfaces of the body which contain such 
clear spots, and they are few in number, are usually dumbbell-shaped in outline, 
and their clear spots are smaller than those of the median tubercles, in which 
they occur more frequently. (2) Smaller, lighter colored tubercles, much 
more variable in form and size than the preceding, and which are irregularly 
arranged between the former kind. In one of the specimens a system of oblique 
lines is seen on the surface of the cuticle, and these lines are peculiar in that 
they do not lie between rows of areoles, but appear to run right across their 
surface (Fig. 117). 

On transverse section of the cuticle two kinds of tubercles are seen, corre- 
sponding to the two kinds seen on surface views (Fig. 116): (1) Low tuber- 
cles of greater diameter, which are flattened apically, and have no projections. 
(2) Tubercles of smaller diameter, very irregular in form, and usually of 
slightly less elevation than the preceding; these correspond to the smaller, 
lighter tubercles seen on surface views. The apex of these is not flattened, but 
more or less irregularly rounded ; from the summit project upwards short 
conical or spiniform processes, which are exceedingly variable in form, some- 
times cleft or pectinate terminally, though most of them are largest at the base 
and pointed at the apex. Rarely is there only a single process to a tubercle : 
as a rule there are a number, and on the tubercles of the dorso-median line of 
the body they are more numerous than elsewhere. In addition to these two 
kinds of tubercles are seen on sections, though only sparsely, hyaline club- 
shaped processes. 

Color of type specimen: black, at the anterior end of the body with a 
reddish tinge ; the tip of the head yellowish white. The second specimen. was 
of a deep rufous-brown color, lighter at the anterior tip of the body, and 
blackish at the posterior end. 

Dimensions. Length of larger individual (type), 255 mm.; greatest diameter, 
1.5 mm. 


52 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


Especial Diagnostic Characters. The presence of two kinds of slightly elevated 
tubercles on the cuticle: tubercles of greater diameter with smooth summit, a 
few of which have an apical clear spot ; and tubercles of smaller diameter and 
usually less elevation, the surface of which is not smooth, but with more or less 
numerous conical or spiniform short processes. 

Comparisons. This species is more closely allied to C. gordioides than to 
any other, but differs from it in the following points : the presence of tubercles 
whose surface bears short processes, the presence of clear spots on the surface of 
some of the smooth tubercles, and the absence of groups of inter-tubercular 
hairs ; there are also differences in coloration, such as the absence of a black 
ring around the mouth aperture, and the much darker color of the body. 


17. C. cubanensis, n. sp. 
Figs. 118-123, Plate 15. 


(Type of Female : Harvard coll. 1466, Cuba. Type of Male: Harvard coll. 
1466 d, Cuba.) 

‘orm of Male. Body nearly cylindrical, without well marked median 
grooves; anterior end slightly attenuated. Head (Fig. 123) very narrow, 
truncated apically, slightly concave on the terminal aspect; on the ventral 
surface alone is there a constriction separating the head from the body. Pos- 
terior end (Fig. 122) flattened on the ventral surface, with a median groove 
behind the cloacal aperture ; this groove is broadest and deepest at the ventro- 
terminal point of the body ; just behind the cloacal aperture is a transverse 
semilunar ridge. 

Form of Female. Larger and more robust than the male, the shape of the 
anterior portion of the body otherwise similar. Head (Fig. 120) rounded at 
the apex, mouth nearer the ventral than the dorsal margin of the head. Pos- 
terior portion of the body (Fig. 121) narrower than the middle, but the 
extreme distal end is swollen, and of greater diameter than the part immedi- 
ately preceding. This posterior end is obliquely truncated, the dorso-terminal 
margin projecting farther caudad than the ventro-terminal; the swelling is 
most pronounced on the ventral side. 

Cuticle (Fig. 119). With papille of three kinds, besides hyaline processes ; 
though it is difficult to distinguish sharply between these kinds since they 
seem to intergrade. The hyaline processes have the same form as in most 
other species of the genus, and are slender club-shaped processes, slightly 
swollen and rounded at the apex ; they are about the height of the highest 
papille. 1st Kind of Papille: The smallest, least elevated, and most numer- 
ous of all occur close together between the groups of larger papille, and also 
in the latter groups. They are pyramidal or somewhat elongate-conical on 
lateral view, pointed at the apex which bears a single (rarely two) long, deli- 
cate, usually curved spine; this spine is thickest at the base and sometimes 
recurved at the tip. A modification of these tubercles attains nearly the height 
of the largest papillw. 2d Kind of Papille: These, the second in point of 


9 


MONTGOMERY: GORDIACEA. 53 


numerical abundance, occur usually in groups close together. ‘They are much 
larger than the preceding, round on cross section, usually considerably longer 
than broad, slightly thickened at the base but with nearly parallel sides, and 
with rounded summit. In a few cases the sides of these papille may be some- 
what denticulate. On the margin of the rounded or flattened apex occur from 
three to six short thick spines, which are broadest at the base and pointed 
at the tip; these spines curve upwards and outwards, and are shorter and 
thicker than those of the preceding category of papille. These papille vary 
considerably in form, and sometimes are nearly square in lateral outline. 
3d Kind of Papille: These are of the same form and size as the preceding, 
but are less numerous (the groups which they compose are smaller), and differ 
from them in the absence of spines on their summits; the apex of most of them 
is elliptically rounded, rarely flattened, and then somewhat denticulate with 
short conical processes; some of these papille are expanded at the summit. 

On surface views (Fig. 118) of the cuticle, seen with a low power of magnifi- 
eation, only the second and third kinds of papillz are seen, and they appear as 
small brown disks with a clearer central point. The cuticle of the male differs 
from that of the female only in that the larger kinds of papillz are less 
abundant, and the groups formed by them smaller. 

Color. The males are uniform pitch-black, the head somewhat lighter ; in 
the female the whole body is deep black. 

Dimensions. Length of largest male, 165 mm.; greatest diameter, 1 mm. 
Length of female, 280 mm.; greatest diameter of body, 1.6 mm.; greatest 
diameter of tail swelling, 1 mm. 

Especial Diagnostic Chayacters. The dense arrangement of the usually 
pencil-shaped papille, and the union of the larger of them into large and 
irregular groups, together with the black color of the body, serve to distinguish 
this form. 

Comparisons. In color this species resembles C. brasiliensis Janda, and 
C. feste Camer. ; but it differs from the former as well as from C. morgani, n. sp., 
in the form and arrangement of the papille. In the structure of the cuticular 
papille it also differs from feste, judging from Camerano’s description: but 
unfortunately most of the South American Gordiacea described by this author 
have not been figured, and for a clear understanding of the form and arrange- 
ment of areoles and papille figures are absolutely necessary. j 


Postscript. — The preceding descriptions of body form, color, and dimen- 
sions have been based entirely upon a study of alcoholic specimens, with the 
consequence that the particulars in regard to coloration and dimensions could 
be only approximately ascertained, since the action of the alcohol would prob- 
ably produce shrinkage, and certainly obscures the brightness of the coloration. 
Formaline would probably be a superior fluid for the preservation of museum 
specimens. For purposes of histological fixation rapidly penetrating fluids are 
necessary, such as picro-formaline or picro-nitric acid. 

VOL. XXXII. — NO. 3. 3 


54 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


APPENDIX. 


Since the preceding was sent to press (on the 16th August, 1897) I have re- 
ceived from Professor Camerano the following important contribution by him: 
“Monografia dei Gordii” (Accademia Reale delle Scienze di Torino, 1897). 
This paper furnishes descriptions and revisions of all known species of Gordi- 
acea, with illustrations of all those described by Camerano, and is especially 
valuable on this account from the systematic standpoint. To the already 
known genera Gordius and Chordodes, this author adds two others, namely, 
Paragordius and Parachordodes. Paragordius embraces, according to Camerano, 
G. tricuspidatus (Dufour), G. emeryi Cam., G. stylosus Linstow, and G. varius 
Leidy. He characterizes it as follows: “ L’ estremita posteriore del ¢ é bifor- 
cata al di 1a dell’ apertura postcloacale con lobi profondamente separati fra 
loro: non vi é lamina cutanea postcloacale. L’ estremita posteriore della 9 @ 
divisa in tre lobi postcloacali profondamente separati fra loro i quali circondano 
V apertura cloacale. Lo strato cuticolare esterno presenta delle formazioni 
areolari di una sola seria e pochissimo sporgenti, irregolarmente disposte: non 
vi sono granuli o tubercoli rifrangenti interareolari.’ By an unusual coinci- 
dence, I had in the preceding pages proposed the same name, Paragordius, to 
include Leidy’s species Gordius varius, so that independently of one another 
Camerano and I have founded a new genus, and given it the same name for 
the same species. By the rules of priority in nomenclature, however, Camerano’s 
publication having appeared first, the genus must stand Paragordius Camerano, 
not Montgomery. But the diagnostic given by Camerano for this new species 
is not very well chosen, for in it the only character of possible genetic value 
mentioned is the trilobation of the posterior end in the female; this character 
is of doubtful generic value, since in Gordius tolosanus Duj. the posterior end 
of the female is somewhat lobed, though in this case the lobation is gener- 
ally regarded as only a specific character! I think the characters described 
above by me as diagnostic of the new genus, —namely, the structure of the 
cloaca in the female and the absence of a cloacal musculature in the male, — are 
of higher value, and accordingly should constitute the diagnostic of the genus. 
The second new genus of Camerano is characterized thus (Parachordodes): 
‘«Estremita posteriore del 3 biforcata al di 14 apertura cloacale, con lobi pro- 
fondamente separati fra loro: nessuna lamina-cutanea postcloacale. L’ es- 
tremita posteriore della 9 @ intiera coll’ apertura cloacale mediana collocata in 
un soleco dorso ventrale pi o meno profondo. Strato cuticolare esterno meno 


MONTGOMERY: GORDIACEA. 55 


complicato che nel genere Chordodes: ora con una sola sorta di formazioni 
areolari, ora con formazioni areolari di due sorta: le une piu basse e chiare: e 
le altre un po’ piu elevate e scure che stanno intorno allo sbocco dei canaletti 
che attraversano gli strati cuticolari: fra le areole spesso vi sono granuli o 
tubercoli rifrangenti.” Parachordodes thus differs from Gordius merely in re- 
gard to cuticular structures, and I cannot consider that such differences warrant 
the separation of a new genus. For in the Gordiacea the cuticular differences 
have little more than specific value, as is well shown by the fact that the 
cuticle may show marked differences in different individuals of the same 
species. If more important differences than these be subsequently determined, 
then, and not until then, does it seem justifiable to me to recognize Parachor- 
dodes as a well defined genus; and hence it should for the present be retracted 
into Gordius, (A preliminary to this monograph was published by Camerano 
in the Zool. Anzeiger for August, 1897, with the title “ Nuova classificazione 
dei Gordii.”) In this paper are given figures of the cuticle of Chordodes 
talensis Cam., which represent its structure as quite different from that of my 
new species, C’. puerilis. 

Here may also be mentioned certain papers on American Gordiacea which 
had been omitted in the preceding pages. 

Girard (1851, “ Historical Sketch of Gordiacea,” Proc. Acad. Nat. Sci. 
Philadelphia, 5) mentions a specimen caught at Richmond, Virginia, and 
several collected in Oregon by the U. 8S. Exploring Expedition. 

Sanford (1853, ‘‘On some Points in the History of Gordius,” Proc, Amer. 
Assoc. Sci.) collected some specimens from crickets (Gryllidez). 

Thompson (1853, “ History of Vermont,’’ Burlington) states that Gordii are 
very common in still waters and mud in that State. 

White (1859, ‘‘ Gordius trifurcatus, n. sp.,” Proc. Boston Soc. Nat. Hist., 7) 
gives the following description, of this species, which may possibly be referable 
to the 9 of Paragordius varius (Leidy): ‘ Male. Length, 5 inches; diameter, 
+ line; shape uniformly cylindrical; head obtusely conical; posterior end 
divided into two long and narrow lobes, and one shorter and broader lobe, in- 
curved and friyged with short thick hairs. At base of larger lobe is the genital 
opening, from which the spermatozoa are seen escaping with extremely long 
tails. Color uniformly light brown. . . . It does not answer to either of the 
two described by Dr. Leidy.” 

Clementi (1869, “ Hair Snakes,” Canadian Entomologist) found Gordii (?) 
in a large spider. 

Leidy (1870, ‘*‘ The Gordius, or Hair-worm,” Amer. Entomol. and Botanist, 2 
gives a good description and some figures (the only figures published by him 
of members of this group) of his G. varius. He considers the males of this 
form, as previously described by him, to be really of two different species: in 
the one (varius) the forks of the tail are thick, with a crescentic fold above the 
genital pore. In the other males (G. longilobatus, n. sp.) “ the forks of the tail 
are two or three times the length of the thickness of the body, and the forks do 
not include at their base a crescentic fold as in the former.’”? (The male here 


56 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
termed “varius” is really G. aquaticus robustus, while “longilobatus” is the true 
Paragordius varius.) 

Leidy (1871, “ Notice of some Worms,” Proc, Acad. Nat. Sci. Philadelphia) 
describes as “Gordius lacustris” several specimens from Kansas; but “‘lacus- 
tris” is certainly a misprint for “robustus,” since the papers to which he refers 
for the preceding name make no mention of it. 

Garman (1886, “ Amblystoma and Gordius,” Science Observer, Boston Sci. 
Soc., cited by Camerano) mentions a Gordius found in Amblystoma. 


MONTGOMERY: GORDIACEA. 57 


LITERATURE LIST. 


Baird, W. 
53. Descriptions of some new Species of Entozoa, from the Collection of 
the British Museum. Proc. Zodél. Soc. London, 21. 


Camerano, L. f 


90. Intorno ad una specie di Gordius (G. eneus Villot) raccolta dal Sig. 
G. B. Anselmo in Venezuela e intorno alle specie di quaesto genere fino 
ad ora descritte dell’ America meridionale. Ann. Mus. Civ. Genova, 
(2) 10. 
Camerano, L. 
92. JDescrizione di una nuova specie del genere Gordius di Palmeira (Parana) 
raccolta dal Dott. Franco Grillo. Ibid. 


Camerano, L. 
°93. Sur quelques Gordiens nouveaux ou peu connus. Bull. Soc. Zool. 
France, 18. 


Camerano, L. 
°94. Viaggio del dottor Alfredo Borelli nella Republica Argentina e nel 
Paraguay. Boll. Mus. zool. Anat. comp. Torino, 9. 


Camerano, L. 
795. Description d’une nouvelle espéce de Gordius du Chili. Actes de la 
Soe. Sci. du Chili, 5. 


Camerano, L. 
’96. Descrizione di una nuova specie di Gordio del Basso Beni (Bolivia) 
raccolta dal Prof. L. Balzan. Ann. Mus. Civ. Genova, 16 (36). 


Camerano, L. 
’97*. Viaggio del Dr. Enrico Festa nella Repubblica dell’ Ecuador e regioni 
vicine. Boll. Mus. Zool. ed. Anat. comp. Univ. Torino, 12. 


Camerano, L. 
97>. Viaggio del Dott. Alfredo Borelli nel Chaco boliviano e nella Repub- 
blica Argentina, Gordii. Ibid. 


Creplin, C. H. 
47. In Froriep’s Notizen a. d. Gebiete d. Natur- und Heilkunde, Weimar, : 
55. 


58 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


Diesing, K. M. 
51. Systema helminthum. Vol. 2. Vindob, 
Diesing, K. M. 
°61. Revision der Nomatoden. Sitzb. k. k. Akad. Wiss. Wien, 42. 
Gay, C. 
48. Historia fisica y politica de Chile, ete. Zoologia, Tom. 3. Paris. 
Goeldi, E. A. 
794. Breva noticia acerca de alguns Vermes interessantes do Brazil. Bol. 
Mus. Paraense, 1. 
Janda, J. 
93. Beitrige zur Systematik der Gordiiden. Spengel’s Zool. Jahrb., Abth. 
f. System., 7. 
Jeffrey-Bell. ' 
’85. Note on a Nematode Worm obtained by M. H. H. Johnston on Kili- 
manjaro- Proc, Zodl. Soc. London. 
Leidy, J. 
°50. Note on the Development of Gordius aquaticus. Proc. Acad. Nat. Sci. 
Philadelphia, 5. 


Leidy, J. 
°51. Gordiacee. Ibid. 
Leidy, J. 
753. A Flora and Fauna within Living Animals. Smithsonian Contribu- 
tions, 5. 
Leidy, J. 


’56. A Synopsis of Entozoa and some of their Ecto-congeners observed by 
the Author. Proc. Acad. Nat. Sci. Philadelphia, 8. 
Leidy, J. 
57. (No title.) Ibid. 
Leidy, J. 
*58. Contributions to Helminthology. Ibid. 
Leidy, J. 
°79. On Gordius and some Parasites of the Rat. Ibid., and Ann. Mag. Nat. 
Hist. 3. 


Mobius, K. 
55. Chordodes pilosus, ein Wurm aus der Familie der Gordiaceen. Zeit. 
wiss. Zool., 6. 
Montgomery, T. H., Jr. 


98. Descriptions of two new Exotic Species of Chordodes. Spengel’s Zool. 
Jahrb. 


Oerley, L. 


*81. On Hair-worms in the Collection of the British Museum. Ann. Mag 
Nat. Hist., (5) 8. 


MONTGOMERY : GORDIACEA. 59 


Romer, F. 
95. Die Gordiiden des Naturhistorischen Museums in Hamburg. Spengel’s 
Zool. Jahrb., Abth. f, System., 8. 
Romer, F. 
796. Beitrag zur Systematik der Gordiiden. Abh. Senckenberg. naturforsch. 
Ges., 23. 
Schneider, A. 
766. Monographie der Nematoden. Berlin. 
Villot, A. 
°74. Monographie des Dragonneaux (Genre Gordius, Dujardin). Arch. 
Zool. gén. et expér., 3. 
Villot, A. 
87. Révision des Gordiens. Ann. Sci. Nat, (7), 1. 


Weyenbergh, D. H. 
°79. Descripciones de nuevos Gusanos. Bol. Acad. Nac. Cienc. Argentina, 3. 


MontTeomery. — Gordiacea. 


EXPLANATION OF THE PLATES. 


All the figures have been drawn with the aid of the camera lucida, unless other- 
wise specified. The microscope and lenses of Zeiss were used; almost all the 
contour figures of the body have been drawn with oc. 2, obj. A; and the majority 
of the surface figures of the cuticle with oc. 4, obj. C. 


PLATE 1. 
Gordius aguaticus robustus. 


Fig. 1. Male, ventral view of posterior end (A, 4). 

Fig. 2. Idem, head end (A, 2). 

Fig. 3. Male, oblique ventral view of posterior end (Harvard coll. 290, A, 2). 

Fig. 4. Lateral view of the preceding, from the left side. 

Fig. 5. Male, ventral view of posterior end (A, 2). 

Fig. 6. Male, ventral view of head end; the transverse curved line shows the 
posterior extension of the white area (A, 2). 


* 
a nial 
————< eee 


Paar: 


B Meisel hth, Sestea 


MontTcomery. — Gordiacea. 


Fig. 7. 
Fig. 8. 
Fig. 9. 
Fig. 10. 


Fig. 11. 
Fig. 12. 


PLATE 2. 
G. aquaticus robustus. 


Female, ventral view of posterior end; a portion of the brown ring around 
the anus is to be seen (A, 2). 

Female, posterior end, showing the ring of brown color around the cloacal 
aperture (A, 2). 

Male, antero-ventral view of the head end, showing the grooves on the 
surface (A, 2). 

Idem, lateral view. 

Female, head end (A, 2). 

Surface view of the cuticle, Canada balsam, the finest lines drawn only in 
one portion ((, 4). 


PLATE 2, 


B Meisel lith Beste 


Fig. 


MontTGomery. — Gordiacea, 


no: 


PLATE 3. 


G. aquaticus robustus. Surface view of the cuticle of a male, the intra- 
rhombic intersecting lines not reproduced (C, 4). 

G. aquaticus difficilis, n. subsp. Male, head end, from the type (A, 2). 

Idem, oblique lateral view of the posterior end (A, 2). 


Figs. 16-19, G. aquaticus robustus. 

Male, surface view of the cuticle, Canada balsam (C, 4). 

Female, head end (A, 2). 

Male, cross section through the body in the plane of the cloacal aperture. 
Cut., cuticula; Epi., epidermis ; Musc., longitudinal musculature of the 
body wall; Cl. Musc., cloacal musculature ; Cn. t., connective tissue ; 
N., branches of the ventral nerve chord; C/. Ap., cloacal aperture 
(GC, 2). 

Male, ventral view of posterior end (A, 2). 


B Meise me 
deisel] Wh & 
WN 


MonTGoMERY. — Gordiacea. 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


Fig. 


Fig. ¢ 


PLATE 4. 


Figs. 20-31, Gordius lineatus Leidy. 


Female, antero-ventral view of head end (A, 2). 

Male (type), head end (A, 2). 

Female (type), lateral view of posterior end (A, 2). 

Female, posterior end, the cloacal epithelium apparently extruded (A, 2). 

Male (type), lateral view of the posterior end (A, 4). 

Idem, ventral view (A, 2). 

Male, oblique lateral view of posterior end (A, 2). 

Male, ventral view of posterior end (A, 2). 

Female (type), termino-ventral view of posterior end, showing the colored 
ring around the cloacal aperture (A, 2). 


. Male (type), transverse section of the cuticle (immers. +5, 2). 


Idem, surface view (C, 4). 
Male, surface view of cuticle (C, 4). 
Female, transverse section of cuticle (immers. 75, 2). 


Figs. 32, 38, G. densareolatus, n. sp. 


Female, surface view of cuticle (C, 4). 
Transverse section of the cuticle of the same specimen (immers. 75, 2). 


B Meisel th Sester 


MontGomMERY. — Gordiacea. 


Fig. 34. 
Fig. 35. 
Fig. 36. 
Fig. 37. 
Fig. 38. 
Fig. 39. 


PLATE 5. 
G. densareolatus, 0. sp. 


Female, head end (A, 2). 

Female (type), head end (A, 2). 

Male (type), oblique lateral view of posterior end (A, 2). 

Idem, ventral view. 

Female (type), posterior end (A, 2). 

Female, posterior end rendered transparent by cedar oil, the intestine and 
a portion of the atrium and oviducts are seen. The transverse line 
represents the edge of the extruded cloacal epithelium (A, 2). 


'GOMERY-GORDIACEA. 


B Meisel hth dastes. 


Monteomery. — Gordiacea, 


PLATE 6. 
G. platycephalus, n. sp. 


Fig. 40. Male (type), head end (A, 2). 

Fig. 41. Idem, ventral view of posterior end (A, 2). 

Fig. 42. Female: a, oblique ventral view of posterior end; 2, dorsal view of 
end; c, lateral view of head end (A, 2). ; 

Fig. 43. Female (type), ventral view of posterior end (A, 2). Os We 

Fig. 44. Idem, lateral view. ; 

Fig. 45. Female (type), head end seen in its broadest plane of exper (A, 2). 


PLATE 6. 


422 


B Meisel Nth. Bestes 


MontTcomery. — Gordiacea. 


PLATE 7. 


Figs. 46-49, G. platycephalus, n. sp. 


Fig. 46%. Female, surface view of cuticle (C, 4). 
46>, Transverse section of the cuticle of the same individual (immers. 75, 2). 


Fig. 
Fig. 
Fig. 
Fig. 


Fig. 


Fig. 
Fig. 


Fig. 
Fig. 
Fig. 


47. 
48. 
49. 


50. 


51. 
52. 


55. 
54 


55. 


Female (type), surface view of cuticle (C, 4). 
Female, transverse section of cuticle (immers. ;4, 2). 
Male (type), transverse section of cuticle (immers. ;4, 2). 


Figs. 50-52, G. platyurus Baird. Female. 


Surface view of cuticle, the finest intersecting lines reproduced at only 
one place (C, 4). 

Posterior end, free hand drawing. X about 4. 

Head end (A, 2). 


Figs. 53-55, G. leidyi, n. sp. Female. 
Dorsal view of the head (A, 2). 


Transverse section of the cuticle (immers. 75, 2). 
Surface view of cuticle (C, 4). 


> —S. » Yo “a ae Fy 


on 


/Montcomery- GORDIACEA. le 
, 
. Cond 2ZQ90 
| re ee SP Ee ERIOBP 
pera tes Jae COED AI “EZ 
. Si 
OCEQWO 
en 
I. > 
48. 


b. 7 - 
¢ a i, 
50. = 
EPS eee, 
I4- 
Sele) 
SBP 
B Meisel lth Sestes 


a 


PLATE 8. 


Figs. 56-59, G. leidyi, n. sp. Female (type). * 
Fig. 56. Dorsal view of posterior end (A, 2). , 
Fig. 57. Idem, termino-ventral view. ra. 
Fig. 58. Idem, oblique lateral view. of 
Fig. 59. Surface view of cuticle (C. 4). a 


Figs. 60-62, G. violaceus Baird (?). Female (Harvard coll. no. 1465). : 


Fig. 60. Posterior end (A, 2). yi 
Fig. 61. Head end (A, 2). 
Fig. 62. Surface view of cuticle (C, 4). 


BR Meisel bth Sester 


ye 


Montecomery. — Gordiacea. 


Fig. 
Fig. 
Fig. 


Fig. 


Fig. 


Fig. 
Fig. 


63. 
64. 
65. 


66. 


67. 


68. 
69. 


PLATE 9. 


Figs. 63-66, G. agassizi, n. sp. Male (type). 
Dorsal view of anterior end (A, 2). 
Surface view of cuticle (seen in alcohol, A, 4). 
Posterior end of the body, the tail lobes seen from the right side, the pre- 
ceding portion of the body from the latero-ventral aspect (A, 2). 
Posterior end, tail lobes seen from the termino-dorsal aspect, the preced- 
ing portion of the body from the ventral (A, 2). 


Figs. 67-69, G. capitosulcatus, n. sp. Male (type). 


Terminal aspect of head end, its ventral edge towards the bottom of the 
page (A, 2). 

Surface view of cuticle (C, 4). 

Dorsal view of head end (A, 2). 


B Meise] With, Basten 


Monteomery. — Gordiacea. 


Fig. 70. 
Fig. 71. 
Fig. 72. 


Fig. 73. 
Fig. 74. 


PLATE 10. 


G. capitosulcatus, n. sp. Male (type), oblique ventral view of the posterior 

end (A, 2). 
Figs. 71-74, G. paranensis Camer. 

Female, termino-ventral view of the posterior end (A, 2). 

Male, posterior end: a, oblique ventral view; }, oblique lateral view 
(A, 2). 

Male, head end (A, 2). 

Male, head end (A, 4). 


PLATE 10. 
B Meisel bth, Bester 


be 


GORDIACEA. 


* 


INTGOMERY 


Fig. 
Fig. 
Fig. 


Fig. 


Fig. 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


Fig. 


MontTeomery. — Gordiacea, 


PLATE 11. 


Figs. 75-77, G. violaceus Baird (?). Female, Harvard coll. no. 1466 ec. 


75. 
76. 
TAKE 


78. 


79. 


80. 
81. 
82. 
83. 


84. 


85. 


Latero-ventral view of posterior end (A, 2). 

Head end (A, 2). 

Transverse section of cuticle (immers. ;5, 2). 

Figs. 78-85, Paragordius varius (Leidy). 

Male, transverse section through the plane of the cloacal aperture. Cut., 
cuticle; Epi., epidermis ; M/usc., longitudinal musculature of the body 
wall; Par., parenchym; N., branches of the ventral nerve chord; Cl. 
Ap., cloacal aperture (C, 2). 

Female, transverse section through the body in the plane of the caudal 
ganglion. Cl. Epi., cloacal epithelium ; N. G/., ganglion of the ventral 
nerve chord ; the other lettering as in the preceding figure (C, 2). 

Female, cross section through the tail lobes near their proximal ends; the 
median lobe is on the dorsal side (A, 2). 

Female, cross section of tail lobes near their distal ends (A, 2). 

Male, oblique dorsal view of head (A, 2). 

Female, head end: a, ventral view; 5, dorsal view, showing two colored 
stripes. The colored ring around the neck is shown in these figures 
(A, 2). 

Female, ventral view of head end; the transverse line shows the posterior 
limit of the white area (A, 2). 

Female, lateral view of head end; the transverse line shows the posterior 
limit of the white area (A, 2). 


ONTGOMERY-GORDIACEA. 


_Phate IL 


Y 


ajier 

TY Eat 
ease 
o. neigh ae 


B Meisel hth Sestee 


Fig. 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


Fig. 
Fig. 
Fig. 


Montecomery. — Gordiacea. 


86. 


87. 
88. 
89. 
90. 
91. 


92. 
93. 
94. 


PLATE 12. 


Figs. 86-93, Paragordius varius (Leidy). 


Optical median section of the posterior end of the female, from a recon- 
struction of sections (A, 2), to show the characteristic length of the 
cloaca. The omitted portion z-y has about ten times the length of 
the portion z-z. T. /., tail lobes; Cut., cuticle; Cl., cloaca; Cl. Ap., 
cloacal aperture; Afr., atrium (uterus) ; Ov. D., left oviduct; Jnt., in- 
testine; Rec. S., receptaculum seminis. 

Male, oblique ventral view of posterior end (A, 2). 

Female, posterior end from the dorsal side (A, 2). 

Female, oblique dorsal view of the posterior end (A, 2). 

Female, dorsal view of the posterior end (A, 2). 

Cuticle of a female: a, transverse section (immers. ;);, 2); 5, surface view 
(C, 4). 

Female, surface view of cuticle (C, 4). 

Male, surface view of cuticle (C, 4). 

Chordodes morgani, n. sp., female (Harvard coll. 1470). Head end from the 
left side (A, 2). 


— ~ we 


MONTGOMERY-GORDIACEA. PLATE 12, 


Vi 


| Bee 8.| + 


THM Jr del. B Meise! bith foster 


Monteomery. — Gordiacea, 


PLATE 13. 


Figs. 95-100, Chordodes morgani, n.sp., female ; 95, 96, from Harvard coll. 1470; 
97-100, from the type specimen. 


Fig. 95. Posterior end from the right side (A, 2). 

Fig. 96. Termino-lateral view of the posterior end (A, 2). 

Fig. 97. Lateral view of the posterior end, right side (A, 2). 

Fig. 98. Head end (A, 2). 

Fig. 99. Transverse section of the cuticle (immers. 75, 2). 

Fig. 100. Surface view of the cuticle, from the side of the body (C, 4). 


Figs. 101-105, b, C. puerilis, n. sp., male. Figs. 101-104, from the type specimen ; 
105, a and b, from a specimen in my possession. 
Fig. 101. Head end, dorsal view (A, 2). 
Fig. 102. Idem, lateral view. 
Fig. 103. Oblique ventral view of the posterior end (A, 2). 
Fig. 104. Surface view of the cuticle (C, 4). 
Fig. 105. Cuticle: a, surface view (C, 4); 5, transverse section (immers. qs, 2). 


Figs. 106, 107, C. gordioides, n. sp., male (type). 


Fig. 106. Transverse section of the cuticle (immers. 75, 2). 
Fig. 107. Surface view of cuticle, the areoles reproduced on only a portion of the ~ 
surface (C, 4). 


3 ane 105% 


/ Da Wr Pn Ta 


| 1054 


B Meise! With Bester 


Fig. 108. 
Fig. 109. 
Fig. 110. 


Fig. 111. 
Fig. 112. 
Fig. 118. 
Fig. 114. 


amy Vaar Fie + P 
Tene ks WAAL aan of je Sh 
my Se ERT 
‘#, Le) cs Vie Lhall 
‘ ‘? an 

, 4 mah ; 

MontTGcomMERY. — Gordiacea, . » a : 

ae: 

a 
PLATE 14. et: 


Figs. 108-110, C. gordioides, n. sp. (types). 
Male, head end (A, 2). 
Female, posterior end: a, ventral view; 5, lateral view (A, 2). 
Male, ventral view of posterior end (A, 2). 


Figs. 111-114, C. occidentalis, n. sp., males. 
Figs. 111, 112, from the type specimen. 


Head end: a, lateral view; }, dorsal view (A, 2). 
Lateral view of posterior end (A, 2). 

Posterior end: a, oblique dorsal view; 4, from the left side (A, PN : 
Head end: a, termino-ventral view ; }, from the left side (A, 2). 


- = 


YNTGOMERY- GORDIACEA. PLATE 14. 


J 
© 


Hd 


LOG! 


1092 


Me M2 


—_ 


M3Ee 44 


B.Mersel ith Sestee 


Fig. 
Fig. 


Fig. 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


MontTeomery, — Gordiacea. 


Figs. 115-117, C. occidentalis, n. sp., males, the first two from the type 


115. 


116. 


I17. 


118. 
119. 
120. 
121. 
122. 
123. 


PLATE 15. 


| 


specimen. 


Surface view of the cuticle, a line passing through z, x shows the median 
plane of the body (C, 4). 

Transverse section through the cuticle in the dorso-median plane of the 
body (immers. +4, 2). 

Surface view of the cuticle; the arrow denotes the line of the transverse 
axis of the body (C, 4). 


Figs. 118-123, C. cubanensis, n. sp. (types). 


Female, surface view of cuticle (C, 4). 

Female transverse section of cuticle (immers. 75, 4). 
Female, head end (A, 2). 

Female, posterior end from the left side (A, 2). 

Male, oblique ventral view of the posterior end (A, 2). 
Male, head end from the right side (A, 2). 


PLate 15. 


$a i. aaa Pet 


B Meisel tith Sestes. 


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. Wives 
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. J v© 
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ra 
. 
. 
: 


Bulletin of the Museum of Comparative Zoology 
i. AP HARVARD COLLEGE 
WiGEstik na AL, Wor 4. 


‘SOME PLANARIANS FROM THE GREAT BARRIER REEF | 
OF AUSTRALIA. 4 


By W. McM. Woopworru. 


Witu OnE PLATE. 


CAMBRIDGE, MASS., U.S. A.: 
PRINTED FOR THE MUSEUM. 
Apri, 1898. 


A 
;, 
x 


No. 4.— Some Planarians from the Great Barrier Reef of 
: Australia. By W. McM. Woopwortu. 


Pseudoceros devisii, sp. nov. 
Fig. 1. 


General color, bright orange-yellow, with a broad marginal band of deeper 
orange and a prominent median dorsal ridge along which the pigment is denser 
than over the general surface of the body, though not so deep in color as the 
marginal band. Length, 33 mm.; greatest breadth, 16mm. From the Brisbane 
River near Brisbane, April, 1896. 

The single specimen of this species, was given to me by Mr. C. W. de Vis, 

t the curator of the Brisbane Museum, in whose honor it is named. The draw- 
ing for the accompanying figure (Fig. 1) was prepared by Dr. A. G. Mayer, 
but unfortunately the specimen was destroyed before it could be preserved, or 
studied in detail. The color and brilliancy of its markings, however, distin- 
guish it from any described species. 


= - Idioplana australiensis, gen. nov., sp. nov. 

7 Figs. 2-5. 

& General color, bluish to yellowish cream when seen on black background, 
___ more reddish on white background. Small spots of dark reddish brown uni- 
& formly distributed over the dorsal surface except at extreme margin, which 


is free from pigment. Ventral surface without pigment, white. Slightly 
translucent ; pharynx and male organs indistinctly visible, the vasa deferentia 
together with the penis forming a Y-shaped figure (Fig. 2). Expanded ante- 
¥ riorly, with a deep median fold or notch. Anterior or expanded portion pro. 
vided with marginal eye-spots extending backwards to a distance about one 
third the total length of the animal from the anterior end. No marginal eye- 
spots in anterior median notch. Two tentacles, situated about one sixth the 
total length from the anterior end ; anterior faces of tentacles provided with 
eye-spots, and a scattered group of eye-spots over the brain region extending 
as far forwards as a line joining the tentacles (Fig. 3). Length 50 mm.; 
greatest breadth 22 mm. A very sluggish form. Only one specimen, taken 
on the reef at Hope Island, May 12. 

The genus Idioplana differs from other Planoceride chiefly as regards the 


sexual organs, The closely approximated sexual openings lie in the anterior 
VOL. XXXII. — NO, 4. 


64 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


part of the posterior third of the body, and in the preserved specimen the 
male gonopore was at a distance of less than 1 mm. from the female open- 
ing. There is a large muscular penis enclosing a spacious prostate gland 
(“ Kérnerdriise”), which communicates with the ductus ejaculatorius at the tip 
of the organ, the two ducts opening to the exterior almost together (Fig. 5). 
The ciliated ductus ejaculatorius extends along the ventral wall of the penis, 
at the posterior end of which it divides into two vesicule seminales, convo- 
luted tubes with muscular walls (not well shown in the diagram, Fig. 4). The 
vasa deferentia are two large convoluted canals of nearly uniform calibre which 
connect with the vesicule seminales at the root of the penis. There are also 
two smaller posterior seminal canals which unite with the main anterior canals 
immediately before these join the vesicule seminales (Fig. 4). As the speci- 
men was in a late stage of sexual activity, no trace of the testes could be found, 
and the vasa deferentia were only partly filled with spermatozoa. 

The female gonopore leads into a spacious bursa, from which the vagina, 
with diminishing calibre, leads upward and backward over the male organ, 
and receives the oviducts which open into it opposite to one another at a point 
above the posterior limits of the penis. The canal, which is ciliated through- 
out, and which from now on is reduced in diameter and uniform in calibre, 
passes forwards and downwards over the penis, reaching nearly to the ventral 
wall, and then bends upwards and backwards again, passing over the vagina 
and terminating a little posterior to the female gonopore in a vesicle or 
enlargement, ‘‘accessorische Blase ” (Figs. 4 and 5). 

The terminology employed in the description of the sexual organ of this 
species is not that which is customarily used in descriptive anatomy of Poly- 
clads, but corresponds to the terminology applied to Triclads. The so called 
“‘ accessory vesicle” I believe to be directly homologous with the uterus of Tri- 
clads, and that fertilization takes place in it. Although the single specimen of 
the species under consideration was far advanced sexually, there was still a 
packet of spermatozoa in the uterine vesicle, and Plehn? has figured the uterine 
vesicle of Latocestus atlanticus containing both ova and spermatozoa. 


Diposthus corallicola, gen. nov., sp. nov. 
Figs. 6-11. 


Color, yellowish rose; very opaque except at margin, which is bluish and 
very translucent. Of the internal organs the position of the pharynx only can 
be seen as a lighter ragged median streak. Two closely approximated groups 
of eye-spots about one tenth the total length of the animal from the anterior 
end. Two pointed conical tentacles close to anterior margin. Length, 15-40 
mm.; greatest breadth, 6-13 mm. Abundant under coral rock on reef at Hope 
Island, May 12. <A very active form. 


1 Plehn, M. Nene Polycladen gesammelt von Herr Kapitan Chiercha, etc. Jen. 
Zeitschr. f. Naturw., Bd. XXX. p. 160, Taf. XI. Fig. 10, 1896. 


nae Die 


WOODWORTH: SOME PLANARIANS FROM AUSTRALIA. 65 


The peculiarities of the male sexual organs of this form have necessitated 
the establishment of a new family for its reception (Diposthide). The salient 
feature is the separation of the penis and prostate gland into two distinct 
organs, both of which are doubtless intromittent. The prostate gland 
(“Kornerdriise”) occupies the male genital atrium together with the penis, 
and lies posterior to it directly over the gonopore. It is slightly larger than 
the penis, and both organs are nearly pendent or perpendicular in position 
(Figs. 8, 9,and 11). The prostate gland is provided with a heavy layer of 
circular muscles, which together with the epithelial covering of the organ 
decrease in thickness toward the free end, and at the very tip are entirely 
lacking. I could not satisfy myself that there was an opening at this point, 
nor could I demonstrate any distinct lumen, which is explicable, possibly, by 
the fact that all of the specimens were in a late stage of sexual activity, all 
traces of testes, vasa deferentia, ovaries, and oviducts having disappeared. Two 
kinds of nuclei occur in the prostate gland, deeply staining nuclei which are 
found chiefly under the zone of circular muscles, and more lightly staining 
granular ones, which are accumulated at the free end of the organ (Fig. 9). 
The latter kind I am inclined to look upon as belonging to the glandular cells 
of the prostate. There are two large vesicule seminales the ducts of which 
unite to form the ductus ejaculatorius (Fig. 11). The seminal vesicles were 
filled with spermatozoa. The female gonopore opens into a large atrium, the 
walls of which are thrown into folds, and into which numerous unicellular 


‘glands, the shell glands, open. The walls of the chamber are also highly 


muscular, to function doubtless as a bursa copulatrix. Two of the specimens 
that were sectioned showed remains of uterine vesicles. One specimen exhib- 
ited two pairs of vesicles, and in the other there were three vesicles on one side 
of the body and two on the other side, with a third duct which ended abruptly, 
indicating the atrophy of the third vesicle of that side. In the specimen with 
but two pairs of uterine vesicles the vesicule seminales had also disappeared, 
but their ducts could be traced back for a considerable distance from the penis. 
The full number of uterine vesicles can only be determined from material in an 
earlier stage of sexual activity. 

The uterine vesicles cannot be compared exactly ‘with the uterine glands fig- 
ured by Lang?! for Oligocladus sanguinolenta, for in that species they are 
only indirectly connected with the uterus by means of the oviducts. They 
are better comparable with the uterine vesicles of Uteriporus vulgaris of Ber- 
gendal,? and I look on the uterine vesicles of Diposthus as different chambers 
of a multipartite uterus, having at least six such parts. The vesicles of each 
side of the body communicate with a common duct, the duets of opposite sides 
uniting to enter the female genital atrium (Fig. 11). As evidence that the 


1 Lang, A. Die Polycladen, Fauna u. Flora des Golfes y. Neapel, Monog. XL, 
Taf. XXIII. Fig. 8. 1884. 

2 Bergendal, D Studier Ofver Turbellarier. II. Om Byggnaden af Uteriporus, 
ete. Lunds Univ. Ars-Skrift, Fys, Siillsk. Handlingar, Bd. VII. 1896. 


' a ; Gs : 
SE ay fine © wa 
>a x 
66 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


uterine vesicles are but separate chambers of a compound organ, is the simul- 
taneous occurrence in these chambers of both ova and spermatozoa. Figure 
10 represents a section through one of the uterine vesicles, showing an ovum 
surrounded by a dense mass of filaments, which in every way resemble the 
‘spermatozoa found in the seminal vesicles of the same specimen. Lang (op. cit., 
p- 297) speaks of skeins of fine filaments resembling spermatozoa in the acces- 
sory vesicles, and of “lumps” which he doubted not were fragments of eggs 
that had found their way in there, 


——— a 


ines aE 
Fig. 2. 
Fig. 3. 
Fig. 4. 
Fig. 5. 
Fig. 6 
Hic. 7 
Fig. 8 
Fig. 9 
Fig. 10 
Fig. 11 


WOODWORTH : SOME PLANARIANS FROM AUSTRALIA. 67 


EXPLANATION OF THE PLATE. 


ABBREVIATIONS. 
dt. ejac. Ductus ejaculatorius. ut. Uterine vesicles. 
gl. pr. Prostate gland. vag. Vagina. 
gl. sh. Shell gland. v.d. Vasa deferentia. 
ov. Ovum. ves. Uterine vesicles. 
ov'dt. Oviduct v. sem. Vesicule seminales. 
pe- Penis. é Male gonopore. 


sp’z. Spermatozoa. 2 Female gonopore. 


Pseudoceros devisii, sp. nov. Drawn from life by A. G. Mayer. X 2. 

Idioplana australiensis, gen. nov., sp. nov. From life; slightly enlarged. 

Idioplana australiensis. To show the arrangement of the tentacular and 
epi-cerebral eye-spots. X 4. 

Idioplana australiensis. Diagram of sexual organs.  X 10. 

Idioplana australiensis. A drawing from five longitudinal consecutive 
sections to show the course of the sexual ducts. X 20. 


3. Diposthus corallicola, gen. nov., sp. nov. Drawn from life; natural size. 
. Diposthus corallicola. Anterior end of corrosive sublimate preparation to 


show the arrangement of tentacular eye-spots. X 4. 


. Diposthus corallicola. Longitudinal section through gonopores. X 47. 
. Diposthus corallicola. Enlarged drawing of prostate gland, from same 


section. X 170. 


. Diposthus corallicola. Diagram of sexual organs.  X 50. 
. Diposthus corallicola. Section through a uterine vesicle. > 160. 


Barrier Reef Planarians. 


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Bulletin of the Museum of Comparative Zoology 
AT HARVARD COLLEGE. 
VoL. XXXII. No. 5. 


REPORTS ON THE DREDGING OPERATIONS OFF THE WEST COAST OF 
CENTRAL AMERICA TO THE GALAPAGOS, TO THE WEST COAST 
OF MEXICO, AND IN THE GULF OF CALIFORNIA, IN CHARGE OF 
ALEXANDER AGASSIZ, CARRIED ON BY THE U. S. FISH COMMIS- 
SION STEAMER “ALBATROSS,” DURING 1891, LIEUT. COMMANDER 
Z. L. TANNER, U. S. N., COMMANDING. 


XXIII. 
PRELIMINARY REPORT ON THE ECHINI. 


By ALEXANDER AGASSIZ. 


{Published by Permission of MARSHALL McDONALD and GEORGE M, BOWERS, 
U.S. Fish Commissioners. ] 


Witn THirtTEEN PLATES, 


AND A CHART OF THE ROUTE OF THE “ALBATROSS.” 


CAMBRIDGE, MASS., U.S. A. : 
PRINTED FOR THE MUSEUM. 


Jung, 1898. 


No. 5.— Reports on the Dredging Operations off the West Coast 
of Central America to the Galapagos, to the West Coast of 
Mexico, and in the Gulf of California, in charge of ALEXANDER 
Acassiz, carried on by the U. S. Fish Commission Steamer 
« Albatross,” during 1891, LizuT. CoMMANDER Z. L. TANNER, 
U.S. N., Commanding. 


XXIII. 
Preliminary Report on the Echini. By ALEXANDER AGASSIZ. 


Tue following brief descriptions, accompanied with figures of the 
more interesting species, collected during the ‘ Albatross ” Expedition 
of 1891, are published to prevent possible confusion in the names 
adopted for the new species of sea-urchins, which will appear on the 
Plates preparing for the final Report. 

As regards the distribution of Echini in the Pacific, we have at the 
present day a condition of things very similar to that which must have 
prevailed in the Atlantic when the species of Echini living in the Crag 
and in the Maltese beds had their representatives in the West Indies, 
having, as has been suggested, found their way from the Mediterranean 
along the shores of an ancient continent. Some of the species living 
on the west coast of Central America have a very extended geographi- 
cal distribution in the Pacific, and yet no one claims that this great 
range has been brought about by their migration along the shores 
of a continent, or continental islands, existing between Panama and 
the Sandwich Islands or the Marquesas. 

The great equatorial current gives us a cause fully efficient to effect 
such a wide distribution, and that in a comparatively short time. While 
undoubtedly many of the species of Echini have no pelagic Plutei, and 
are so to speak viviparous, or carry their young for a considerable period, 
yet we should remember that young Echini, even after they have 


assumed the characters of the adult, are capable of being transported 
VOL. XXXII. — NO. 6. 1 


i2 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


long distances by currents. It is not an uncommon thing to find the 
young of Arbacia, of Strongylocentrotus, and of Echinarachnius on our 
coasts floating about, and they are not unfrequently caught in the sur- 
face townet. The same holds good for many species of Starfishes and of 
Ophiurans, as well as of Holothurians. In Florida I have canght in the 
same way the young of Cidaris and Hipponoé, and of Toxopneustes, and 
of many other species of Starfishes and Ophiurans. These young Echino- 
derms all float, and may be carried very long distances during the period 
in which they still have the huge embryonic tentacles characteristic of 
their younger stages, when the ambulacral feet are entirely out of pro- 
portion in size to the rest of the test, and the young thus possess a great 
floating capacity when their suckers are expanded. 

They retain these suckers for a considerable period of time, during 
which they can be transported very great distances. There is no other 
explanation for the identity of the littoral marine fauna of the Bermudas 
than that the young and embryos of the Echinoderms and Polyps of the 
West Indies have been carried northward fully six hundred miles by 
the Gulf Stream at arate of from one to three miles a day, and have 
finally settled in the Bermudas. 

We can well imagine an equatorial current taking during Miocene and 
Eocene periods the young of the Echini flourishing in the Crag and in the 
Mediterranean, and in the southern extension of that fauna perhaps only 
from the Cape Verd Islands, and bringing them to the shores of North- 
ern South America or into the Caribbean Sea. That stretch is but 
little longer than the stretch which we know is annually traversed by 
Acalephs, Pteropods, Fishes, and Annelids, along the course of the Gulf 
Stream from the Straits of Florida to Narragansett Bay, and to the 
southern shores of Cape Cod and the adjacent islands. 

The existence of a continent or of intervening islands does not seem 
to me necessary to explain the similarity of the Echinid fauna of former 
times on both sides of the Atlantic or Pacific. The causes now at work 
appear to me sufficient to explain their relationship, when we take into 
account what is known of the efficient transporting agency of equatorial 
or other oceanic streams for the Pluteus or the young stages of Echini 
during a considerable period of their post-embryonic life. 

We should also remember that, even with our imperfect knowledge of 
the bathymetrical range of Echini, the range in depths of many genera 
is known to be very great, as will be seen from an examination of the 
lists given in the ‘‘ Challenger” Reports and from the depths obtained 
by this Expedition. Among these I may mention those having a great 


ee ee he eel ee el 


AGASSIZ: PRELIMINARY REPORT ON THE ECHINI. t8 


geographical distribution, as well as a wide bathymetrical range. This 
will serve to show the extent to which many species can slowly migrate 
upon the bottom, even at a very considerable distance from land or con- 
tinental or insular slopes, when living in the track of a great equatorial 
current which supplies them with a constant and abundant supply of 
food. 


DESMOSTICHA, HAECKEL. 
CIDARIDZA, MULL. 


GONIOCIDARID AL, Harcse.. 


Dorocidaris panamensis A. Ac. 
Plate I. ; Plate II. Fig. 1. 


The test of this species is greatly flattened; the primary radioles are short, in 
many specimens not longer than the diameter of the test; they are compara- 
tively slender but with a coarser granulation than in the Atlantic species (D. 
papillata). The abactinal system is also smaller, the anal system more pentag- 
onal, and the genital plates more elongate than in the D. papillata, and the 
actinal spines are smaller than in that species. 

Station No. 3367, off Cocos Island, 100 fathoms. 

id * 3368, off Cocos Island, 66 fathoms. 
$6 “ 3378, off Galera Point, 112 fathoms. 
6 “ 3397, off Galera Point, 85 fathoms. 


Goniocidaris Doederleini A. Ac. 
Plate Lil. Fig. 1. 


The nearest ally of this species is G. canaliculata, from which it is readily 
distinguished by the greater flatness of the test and the very slender primary 


Genera. Range in fathoms. Genera. Range in fathoms. 
Suerocidaris . . . . +; 874 Hipponbe: 3). « . » 401 
Porocidaris .... . 1444 BIDWUISrIay ke st sy a OO 
Goniocidaris . . . . . 1975 Pourtalesia, 2 7". .-. -2b50 
Maye). ws sw « 1860 Homolampas. . . . . 1600 
momocidaris . ... . 1075 IMaretia Seas. oe Sos “B00 
Meelopieurds.. . . . . 1828 Echinocardium . . . . 2675 
Aspidodiadema. . . . 1800 Hemingter. so occte,c tw AOD 
Dermatodiadema . . . 800 Brissopsis. . . . . « 24865 
Phormosoma. . . . . 1100 PARTON ion unt op RNS anne LODO 
Temnechinus ... . 600 Cystechinus ... .. ~« 900 
Trigonocidaris . . . . 460 Wreehinus'.5).. i. sas). 0). G00 
MeOMInOB 4... « . '. 2400 Perinsten) sc h- .ohs ey er SOO 


Spherechinus ... . 400 Schizaster. . . .. . 1400 


74 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


radioles. When alive the bare spaces of the test are of a deep brownish violet, 
the primary spines reddish, and the miliaries greenish with brownish longitu- 
dinal bands. The sutures of the genital and ocular plates are marked by a 
sharp violet line and the genital system is comparatively bare and free from 
miliaries. 

Station No. 3369, off Cocos Island, 52 fathoms. 


Two new species of Porocidaris were dredged by the “ Albatross.” 


Porocidaris Milleri A. Ac. 
Plate IV. 


This species is closely allied to P. elegans collected by the ‘‘ Challenger.” Its 
radioles differ from those of the Challenger species in having finer serrations. 
The actinal system is marked for the prominent development of the interam- 
bulacral plates, while in P. elegans the actinal system is paved with ambulacral 
plates (Agassiz, Chall. Echini, Plate III. Fig. 3). The primary tubercles of 
this species are not crenulate as they are in the other species of the genus, but 
the species possesses the remarkable primary actinal radioles which are so char- 
acteristic of the genus. The median interambulacral suture is bare of miliaries, 
while in P. elegans the presence of the closely packed miliaries conceals the 
suture. 

Station No. 3359, off Cape Mala, 465 fathoms. 

x “ 3360, off Cape Mala, 1672 fathoms. 

“4 * 3381, off Malpelo Island, 1772 fathoms. 
“ 3399, off Galera Point, 1740 fathoms. 

+ 3415, off Acapulco, 1879 fathoms, 


Porocidaris Cobosi A. Ac. 
Plate ITI. Figs. 2-5. 

This species is readily recognized by its comparatively small actinal and 
abactinal system. The primary radioles recall those of the Atlantic species 
P. Sharreri. In the ambulacral zone the primary miliaries are larger than 
those surrounding the scrobicular area of the primary tubercles in the interam- 
bulacral area. The primary mammary bosses are perforated and crenulated ; 


the scrobicular area is narrow. 
Station No. 3404, off Chatham Island, 385 fathoms. 


SALENIDZE, Aaass. 


Salenia miliaris A. Ac. 
Plate II. Figs. 2-4. 


This species can at once be distinguished from its Pacific congeners by the 
great size of the anal system, which is irregularly hexagonal and covered with 


a 


AGASSIZ: PRELIMINARY REPORT ON THE ECHINI. 75 


a comparatively larger number of plates than in the other pacific species. The 
primary radioles are marked for the great development of the milled ring. 
The primary ambulacral tubercles are small and the two vertical rows are sepa- 
rated by a wide band crowded with minute miliaries. Some of the primary 
radioles are curved at the extremity and their great length is very striking. In 
a specimen measuring 12 mm. in diameter, the radioles were slightly over 
60 mm. in length. 
Station No. 3357, off Mariato Point, 782 fathoms. 

G «3360, on way to Cocos Island, 1672 fathoms. 

« “ 3361, on way to Cocos Island, 1471 fathoms. 

& “ 3362, on way to Cocos Island, 1175 fathoms. 

ce “ 3376, South of Malpelo Island, 1132 fathoms. 

66 * 3380, off Malpelo Island, 899 fathoms. 

= «“ 3407, Galapagos Islands, 885 fathoms. 

a “ 3411, Galapagos Islands, 1189 fathoms. 

me “ 3413, Galapagos Islands, 1260 fathoms. 


ARBACIAD 2, PETERS. 


At Station 3382 in 1793 fathoms we dredged a single specimen of a species 
constituting a new genus (Dialithocidaris), and one which we may consider as 
the Pacific representative of Podocidaris of the West Indies. I am inclined to 
consider as also belonging to this genus Podocidaris prionigera A. Ag., which 
when described was referred with considerable doubt to the genus Podocidaris. 


DIALITHOCIDARIS, A. Ac. 


The genus is marked by the great size of the genital and ocular plates of the 
apical system ; by the width of the interambulacral area, by the peculiar 
linear arrangement of the large interambulacral miliaries along the median line 
parallel with the horizontal sutures of the upper interambulacral plates. The 
plates nearer the ambitus and on the actinal surface each carry two primary 
tubercles. The ambulacral plates carry one primary tubercle. The sutures of 
the abactinal coronal plates are somewhat sunken and bare, as in some species 
of Goniocidaris. 


Dialithocidaris gemmifera A. Ac. 
Plate V. Figs. 1, 2. 


There are only four anal plates in the single specimen we dredged. The 
genital and ocular plates are crowded with irregularly arranged sessile spines, 
either globular or clubshaped. The madreporite is well developed. The ac- 
tinal system is marked by ten large elliptical plates placed in the extension of 
the ambulacral system. The longest primary radioles are 8 mm. in length, 


76 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


flattened, fluted and serrated on the edges, and are comparatively smaller and 
more slender than in species of the allied genus Podocidaris. The diameter of 
the test of this specimen was 21 mm. when alive. The color of test and spines 
is yellowish brown. 


DIADEMATIDA, PETERS. 
DERMATODIADEMA, A. Aa. 


This genus holds the same relation to Aspidodiadema which Echinothrix 
holds to Diadema. It differs from it in having only small secondary tubercles 
in the ambulacral areas while in Aspidodiadema there are large primary tuber- 
cles in the actinal region, as in Hemicidaris. 


Dermatodiadema globulosum A. Ae. 
Plate V. Figs. 3, 4. 


Marked for its high test, the five large plates surrounding the anal opening, 
the great width of the ambulacral area, and the stout primary interambulacral 
radioles, and the deep furrows of the scrobicular area. The longest speci- 
men collected measured 22 mm. in diameter, the largest primary radioles are 
nearly twice the length of the diameter of the test. 

Station No. 3381, nerth of Malpelo Island, in 1772 fathoms. 

= “ 3398, off Galera Point, in 1573 fathoms. 


Dermatodiadema horridum A. Ag. 
Plate V. Figs. 5-7. 


This species has a comparatively large apical system. The anal system is 
covered by a large number of small plates, a ring of seven or eight somewhat 
larger plates surrounding the anal opening. The greater number of specimens 
were about 20 mm. in diameter, the apical system measuring 14 mm. across. 
It is probable that Aspidodiadema antillarum, collected by the “Blake,” will 
have to be transferred to Dermatodiadema, the lack of material inducing me 
to associate it with Aspidodiadema, although it possesses the miliary primary 
ambulacral tubercles characteristic of the genus Dermatodiadema. Test dark 
elaret color, primary radioles pinkish. 

Station No. 3362, between Cocos Island and Mainland, in 1175 fathoms. 

a “ 3363, between Cocos Island and Mainland, in 978 fathoms. 

= “ 3364, between Cocos Island and Mainland, in 902 fathoms. 

“ “ 3375, south of Malpelo Island, in 1201 fathoms. 

“< ** 3376, near Malpelo Island, in 1132 fathoms. 

« “3381, north of Malpelo Island, in 1772 fathoms, 

* “ 3398, off Galera Point in 1573 fathoms. 

“ ** 3400, from Galera Point to Galapagos, in 1322 fathoms. 

. “ 3413, northwest of Culpepper Island, Galapagos, in 1360 fathoms. 


AGASSIZ: PRELIMINARY REPORT ON THE ECHINI. 77 


ECHINOTHURIDA, Wrv. THoms. 


Phormosoma panamensis A. Ac. 


The specimens of this species were all in a poor condition ; they are allied to 
Ph. tenuis, but this species is interesting in having on the actinal side the char- 
acters of Phormosoma most decidedly developed, while on the abactinal side the 
great elongation of the ambulacral plates and the arrangement of the coronal 
plates resemble the structural features of Asthenosoma. Better preserved 
specimens may show this species to belong to a new genus of the family 
intermediate between Phormosoma and Asthenosoma. 

Station No. 3374, southwest of Malpelo Island, in 1825 fathoms. 


Phormosoma hispidum A. Ac. 
Plate VI., Plate VII. 


This species is the Pacific representative of the Caribbean and Northern 
Atlantic Ph. uranus; it has like it an extensive geographical range, but in 
comparatively deeper water. The largest specimens collected measured 201 mm. 
in diameter. The test is marked for the great width of the ambulacral sys- 
tem at the ambitus, which is nearly as wide as the adjoining interambulacral 
system. The large primary radioles of the actinal edge are slightly curved and 
tipped. On the abactinal side of the ambitus the coronal plates both ambu- 
Jacral and interambulacral carry only one small secondary tubercle on the 
distal extremity of the plate with a few irregularly scattered miliaries. The 
outer primary row of interambulacral tubercles extends on half the coronal 
plates, the inner row only on two or three of them. 


PETALOSTICHA, HAk&ckKEL. 
SPATANGIDA, AaGass. 
POURTALESIA, A. Aa. 


Pourtalesia Tanneri A. Ac. 
Plate VIII. Figs. 1, 2. 


This species is closely allied to P. laguncula (Challenger Echini, Plate 
XXII Figs. 7-15, Plate XX XI. Figs. 1-11), but differs from it in the shape 
of the test, which is less bottle-shaped, the greater height of the anterior ex- 
tremity of the test, the concentration of the primary tubercles on the sides of 
the test in more or Jess parallel rows in a triangular space extending from the 
anal system to the lower angle of the ambitus, and the greater length of the 


78 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


primary spines on the flanks of the test. The actinal side of the test is flatter 
than in P. laguncula and the proboscis runs at a less angle from the plane of 
that surface. The color of the test is pinkish ; the radioles are white. 
Station No. 3411, between Bindloe and Wenham Islands, in 1189 fathoms. 
* “ 3431, off Altata, Gulf of California, in 995 fathoms. 


PLEXECHINDS, A. Ac. 


Only two specimens of this interesting genus were collected. This genus is 
peculiar as combining some of the features of Urechinus and Pourtalesia. It 
has the flush actinostome of the former genus, and at the apex the widely sepa- 
rated bivium and trivium of Pourtalesia, with simple ambulacral pores, a slightly 
developed anal proboscis, a sunken anal system, and a well developed broad 
subanal fasciole. 


Plexechinus cinctus A. Ae. 
Plate VIII. Figs. 3, 4. 


Seen in profile, the test slopes very gradually from the bivium towards the 
rounded anterior extremity. The posterior end is truncated, deeply scooped 
out above the broad anal proboscis for the reception of the anal system. The 
anal proboscis is rounded, curved back anteriorly, and is gradually lost in the 
keel of the actinal plastron. The anal proboscis is banded by a wide fasciole, 
extending far beyond the posterior edge of the anal system to the keel of the 
actinal plastron. On the actinal side the posterior ambulacral areas are broad 
and bare. At the anterior extremity towards the ambitus the test is closely 
covered by primary tubercles; they become smaller as they pass beyond the 
ambitus and cover the abactinal area, and are quite regularly scattered over the 
test with somewhat distant minute miliaries in the intertubercular spaces. 
The anal system is transversely elliptical, strengthened by eight large trape- 
zoidal plates surrounding the central anal opening. 

Station No. 3424, off Tres Marias, Gulf of California, in 676 fathoms. 


Eckinocrepis setigera A. Ac. 
Plate XIII. 


Although a number of fragments of this species were collected, only a single 
fairly complete specimen was obtained from Station 3399. It measured 99 mm. 
in length, 51 mm. in greatest width, and 53 mm. in height. The test was of 
chocolate color; the primary spines from 20 to 22 mm. long were pinkish, 
This species is at once distinguished from E. cuneata by the great elongation 
of the odd interambulacrum and the more rounded outline of the test, which is 
far less angular than that of E. cuneata (Challenger Echini, Plate XX VII. Figs. 
1-5). The anterior ambulacral groove is but slightly depressed above the 
ambitus; the actinal pouch is entirely on the oral surface, and the anterior ex 


nr 


AGASSIZ: PRELIMINARY REPORT ON THE ECHINI. 79 


tremity does not pass, as in E. cuneata, into the anterior ambulacral groove. 
The actinal system is protected by five large plates. 
Station No. 3398, off Galera Point, in 1573 fathoms. 
AS “ 3399, off Galera Point, in 1740 fathoms. 
“« = 3415, off Acapulco, in 1879 fathoms. 


Urechinus giganteus A. Ae. 
Plate VIII. Figs. 7, 8. 


At Station No. 3431 two specimens of Urechinus were collected, much larger 
than those of any of the species dredged by the “ Challenger ” or the “ Blake,” 
the largest specimen measuring 93 mm. in length, 80 mm. in width, and 39 mm. 
in height. This species is also remarkable for the great length of the primary 
spines, which in proportion to the length of the test are nearly as long as those 
of Linopneustes, Above the ambitus the test is covered by minute miliaries, scat- 
tered uniformly over the surface of the coronal plates. The primary tubercles 
are placed uniformly over the abactinal part of the test both in the ambulacral 
and interambulacral areas. They are somewhat more closely placed near the 
ambitus and in the interambulacral areas of the actinal surface they are closely 
packed, forming a distinct actinal plastron in the odd interambulacrum. 
The phyllodes extend to the sixth or seventh pore from the actinostome. It is 
interesting to note that there are quite well developed “ bourrelets”’ separating 
the ambulacral areas, a feature characteristic of such genera as Conolampas, 
Conoclypus, Echinolampas, and the like. 

Station No. 3431, off Altata, Gulf of California, in 995 fathoms. 


Cystechinus Loveni A. Age. 
Plate IX. 


The test of this species is comparatively stout; it is closely allied to Cyste- 
chinus Wyvillii, but can at once be distinguished from it by its transverse anal 
system (it is longitudinal both in C. Wyvillii and C. clypeatus), by the great 
size of the actinal interambulacral plate of the actinal plastron, and by the strue- 
ture of the apical system which is intermediate between that of C. clypeatus 
and C. Wyvillii (Challenger Echini, Plate XXIX.> Fig. 1, and Plate XXXV.» 
Fig. 10). 

Station No. 3415, off Acapulco, in 1879 fathoms. 


Cystechinus Rathbuni A. Ae. 
Plate X. 

A number of specimens in excellent condition were dredged from the two 
localities at which this species was procured. The test of this species is thinner 
than in C. Loveni, but somewhat thicker than in ©. vesica. A few of the speci- 
mens came up which had preserved their shape, so we are able to give figures 


80 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


of the outlines of the group of Cystechinus allied to C. vestca. The specimens 
collected varied from a brilliant dark violet to a light claret color. 

The anal system is very large, placed well above the ambitus. On the actinal 
side, the primary tuberculation of the test is smaller and less crowded than in 
C. vesica. There are four genital pores in all the specimens collected; another 
feature distinguishing it from C. vesica. 

Station No. 3360, southwest of Mariato Point, in 1672 fathoms. 

[ «3374, southwest of Malpelo Island, in 1823 fathoms. 


ANANCHYTIDA, As. Gras. 
PHRISSOCYSTIS, A. Ace. 


This genus is allied to Paleeotropus and Paleobrissus in having like them a 
simple ambulacral system, without even the slight trace of petaloid arrangement 
found in Palzobrissus, The petals are perhaps even more like those of Cyste- 
chinus, Echinocrepis, Gonicopatagus, Calymne, and the like. At the actino- 
some, however, the phyllodes attain an extraordinary development, recalling 
those of Paleopneustes and Linopneustes. The apical system is compact, 
similar to that of the genera last named, and the primary spines are long and 
curved, recalling those of the same genera. 


Phrissocystis aculeata A. Ac. 
Plate XII. Figs. 1-7. 

Although not a single complete specimen of this species was obtained, a 
sufficient number of larger fragments were collected to enable us to reconstruct 
fairly accurately this interesting sea-urchin. Its general facies must have 
been similar to the species of Linopneustes and of Paleopneustes. The test 
is thin, covered with large distant primary radioles of uniform size. .The 
outline of the test must have been somewhat conical, the apex slightly ee- 
centric posteriorly, the oral plastron very prominent and flanked by the wide 
bare areas of the posterior ambulacra. The apical system compact, with four 
large genital openings ; the madreporic body covers the whole of the posterior 
part of the apical system, and surrounds the anterior genital pores. The ocular 
plates are small but distinct, with large pores. The smaller plates of the 
abactinal part of the ambulacral areas are bare, the larger plates carry first one, 
and at the ambitus there are from eight to ten distant primaries. In the odd 
interambulacrum there is a slight median furrow extending a short distance 
from the apex to the anal system. The whole test is covered with distant 
miliaries irregularly scattered over the coronal plates. The anal system is 
transversely elliptical and protected by a number of irregularly shaped plates; 
the phyllodes are greatly developed. The largest specimens must have been 
100 mm. in length, and 50 mm. in height, and from 80 to 90 mm. in width 
across the anterior half of the posterior interambulacral area. 

Station No, 3366, in 1067 fathoms. 


AGASSIZ: PRELIMINARY REPORT ON THE ECHINI. 81 


Homolampas hastata A. Ae. 


Plate XI. Fig. 1. 


This species is distinguished by the great distinctness and sharpness of its 
peripetalous fasciole, which is somewhat pentagonal in outline, and surrounds 
the few primary tubercles found near the apical extremity. The plates of both 
of the ambulacral and interambulacral areas of the abactinal part of the test are 
covered by small secondaries and miliaries; this tuberculation is closer than 
in any other species of the genus; the posterior extremity is more vertically 
truncated, and the anal groove not so pronounced as in H. fulva. The anal 
system is pyriform, its greatest diameter being transverse, as in H. fragilis. 
There are only two of the larger primary tubercles in the lateral interambu- 
lacra carrying long curved spines. 

Station No. 3363, northeast of Cocos Island, in 976 fathoms. 

ee “© 3365, northeast of Cocos Island, in 1010 fathoms. 
ie “ 3376, South of Malpelo, in 1132 fathoms. 


BRISSINA Gray. 


Aérope fulva A. Ae. 


Plate VIII. Figs. 5, 6- 


This species is readily distinguished from the other species of the genus by 
its proportionally greater length, the lateral flattening of the test, and the 
pointed anal rostrum. The tuberculation is also closer, and the primary spines 
are slender in comparison with the stouter spines of Aérope rostrata. The anal 
plastron is elongate, triangular, closely packed with primaries, the actinostome 
longitudinally elliptical. The anal system is somewhat pyriform, with the 
anal opening in the posterior part of the anal system. 

Station No. 3361, on way to Cocos Island from Mariato Pt., in 1471 fathoms. 

i ** 3362, on way to Cocos Island from Mariato Pt., in 1175 fathoms. 
s ** 3381, north of Malpelo Island, in 1772 fathoms. 

6 “ 3398, off Galera Point, in 1573 fathoms. 

« “ 3399, off Galera Point, in 1740 fathoms. 


Schizaster latifrons A. Ae. 
Plate XI. Figs. 2, 3. 


At Station 3431, in 995 fathoms, were collected specimens of a species of 
Schizaster remarkable for the great development of the anterior extremity, the 
‘breadth of the anterior ambulacrum, and the short posterior pair of ambulacral 
petals. This species belongs to the Schizaster group, of which S. Philippii is a 
well known representative. 


82 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Schizaster Townsendi A. Ag. 


A large series of this species was collected during our cruise from a number 
of localities. It is marked by the flatness of the test and the great width of 
all the lateral ambulacra, the small size of the anal system, the close primary 
tuberculation of the actinal plastron, which is in striking contrast to the bare 
actinal surface. 


Station No. 3394. Gulf of Panama. 511 fathoms. 
“cc “ 3419. “ “ “cc “ 
oe aa ee “ 674. « 

(74 ce 3425. “ “ 680 “ 
“ “ 3426. “ “ 146 “cc 
(74 cc 3431. “ce ee 995 if4 
“cc “ 3436. “ “ce 905 “ 


a “3437. 50 miles south of Guaymas. 628 “ 


Periaster tenuis A. Ac. 
Plate XI. Figs. 6, 7- 


This species is much flatter and less globular than the species from the Gulf 
of Mexico (P. limicola). It has no anal fasciole; the peripetalous fasciole is 
wide, with prominent miliaries; the actinal plastron is elongated, and the 
tuberculation of the test close. In life the color of the test is light brown. 

Station No. 3381. Off Galera Point. 1772 fathoms. 

Fe a oogs. + ds ‘Se 1673 ~ 
“ “e 3399. {it “cc “ee 1743 “ 


Brissopsis columbaris A. Ace. 


The Pacific Brissopsis is readily distinguished from the Atlantic species by 
the great length of the lateral ambulacra, the flatness of the test, and the great 
width of the area enclosed by the subanal fasciole. The anal extremity of the 
test is also more sloping than in the European species, and characterized by 
the great size of the anal system. The great variation found in specimens of 
the genus both on the Atlantic and Pacific sides of the Isthmus of Panama 
leads me to think that there has been some confusion in referring to Brissopsis 
such elongate types of Spatangoids as I figure on Plate XX VI. Figure 7 of the 
Blake Echini.t I shall refer to this again in my final Report on the Albatross 
Echini. 

Station No, 3353. 695 fathoms. 

a *« 3356. Off Mariato Point. 546 “ 
se “ 3382. Off Mala Point. 1798) 9 
is * 3394. Panama Bay. BY oe 


1 Mem. Mus. Comp. Zodl., Vol. X., No. 1, 1883. 


AGASSIZ: PRELIMINARY REPORT ON THE ECHINI. 83 


Toxobrissus pacificus A. Ac. 
Plate XI. Figs. 4, 5. 


There occurs in the Pacific a Spatangoid which has been regarded as allied 
to Brissus. Specimens of it are known to me from the Sandwich Islands and 
from Zanzibar. A species closely allied to the above mentioned specimens has 
been dredged off Point Mala, at Station No, 3355, in 182 fathoms. I am in- 
clined at present to place these specimens in the genus Toxobrissus of Desor. 
The species dredged by the Albatross are marked for the flatness of the test, 
the confluence of the posterior ambulacra along the median line for nearly 
half their length, the great width of the posterior extremity of the test, the 
large and uniform size of the posterior ambulacral plates on the actinal side 
of the test, as well as the small size of the actinal plastron. 


SPATAGODESMA, A. Ae. 


Plate XII. Fig. 8. 


From Station 2769, during the voyage of the “ Albatross” from New York 
to San Francisco, were obtained specimens of a small species of Spatangoid, 
in which the character of the apical fasciole differs widely from that of any 
Spatangoid known to me. It possesses a broad elliptical fasciole encircling 
both the ambulacra and the anal system. A transverse band divides the fas- 
ciole into two areas, one enclosing the anal system and the other becoming the 
peripetalous fasciole. Such a fasciole is unknown to me, and among the young 
Spatangoids I have had occasion to examine nothing similar exists. The near- 
est approach to the fasciole of this genus, for which I propose the name Spata- 
godesma, seems to exist in the young of Agassizia, in which an imperfect 
subanal fasciole branches off from the peripetalous fasciole. The actinostome 
is still quite central, and no prominent posterior labrum is as yet developed in 
the largest specimen, which is about 7 mm. in length. I have not yet been able 
to satisfy myself of the relations of this interesting Spatangoid. 


84 


Fig. 
Fig. 


Fig. 


i—] 


Fig. 
Fig. 
Fig. 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


Fig. 
Fig. 


Fig. 1. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


Svs Ne 


. Porocidaris Milleri A. Ag., (female) test, seen from the abactinal side. 


oe 


BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


EXPLANATION OF THE PLATES. 


PLATE L 


. Dorocidaris panamensis A. Ag., from the abactinal side. 
. Dorocidaris panamensis A, Ag., from the actinal side. 


All figures natural size. 


PLATE II. 


. Dorocidaris panamensis A. Ag., facing the odd anterior ambulacrum, 
. Salenia miliaris A. Ag., abactinal view. 

. Salenia miliaris A. Ag., partly denuded. 

. Saienia miliaris A. Ag., facing the odd anterior ambulacrum. 


All figures natural size. 


PLATE III. 


Goniocidaris Doederleini A. Ag., from the abactinal side. 
Porocidaris Cobosi A. Ag., in profile. 

Porocidaris Cobosi A. Ag., from the actinal side. 

Porocidaris Cobosi-A. Ag., facing the posterior interambulacrum. 
Porocidaris Cobosi A. Ag., from the abactinal side. 


All figures natural size. 


PLATE IV. 


Porocidaris Milleri A. Ag., from the actinal side. 
All figures natural size. 


PLATE V. 


Dialithocidaris gemmifera A. Ag., from the abactinal side. 


. Dialithocidaris gemmifera A. Ag., facing the odd anterior ambulacrum. 


Dermatodiadema globulosum A. Ag., from the abactinal side. 
Dermatodiadema globulosum A. Ag., facing the odd anterior ambulacrum. 
Dermatodiadema horridum A. Ag., from the abactinal side. 


. Dermatodiadema horridum A. Ag., in profile. \ 
. Dermatodiadema horridum A. Ag., facing the left anterior ambulacrum. 


All figures natural size. 


Fig. 


Fig. 


Fig. 


Fig. 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


Fig. 
Fig. 


Fig. 
Fig. 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


GOS SU S2 CO ROS) Rae kat 


AGASSIZ: PRELIMINARY REPORT ON THE ECHINI. 85 


PLATE VI. 


. Phormosoma hispidum A. Ag., from the abactinal side, odd anterior ambu- 


lacrum on the left. 


. Phormosoma hispidum A. Ag., (a larger specimen,) from the abactinal side, 


odd anterior ambulacrum on the left. 
All figures natural size. 


PLATE VII. 


. Phormosoma hispidum A. Ag., (same as Fig. 1, Pl. VI.,) from the actinal 


side, odd anterior ambulacrum on the left. 


. Phormosoma hispidum A. Ag., from the actinal side, odd anterior ambula- 


crum on the left. 
All figures natural size. 


PLATE VIII. 


Pourtalesia Tanneri A. Ag., from the abactinal side. 
Pourtalesia Tanneri A. Ag., in profile. 

Plexechinus cinctus A. Ag., in profile. 

Plexechinus cinctus A. Ag., from the abactinal side. 
Aérope fulva A. Ag., from the abactinal side. 
Aérope fulva A. Ag,, in profile. 

Urechinus giganteus A. Ag., from the abactinal side. 
Urechinus giganteus A. Ag., in profile. 


All figures natural size. 


PLATE IX. 


Cystechinus Loveni A. Ag., in profile. 
Cystechinus Loveni A. Ag., from the abactinal side. 


All figures natural size. 


PLATE X. 
Cystechinus Rathbuni A. Ag., facing the anal system. 


. Cystechinus Rathbuni A. Ag., from the abactinal side. 


All figures natural size. 


PLATE XI. 


1. Homolampas hastata A. Ag., from the abactinal side. 
2. Schizaster latifrons A. Ag., from the abactinal side. 
8. Schizaster latifrons A. Ag., from the actinal side. 

4, 
5 
6 
7 


Toxobrissus pacificus A. Ag., from the abactinal side. 


. Toxobrissus pacificus A. Ag., from the actinal side. 
. Periaster tenuis A. Ag., from the abactinal side. 
. Periaster tenuis A. Ag., from the actinal side. 


All figures natural size. 


VOL. XXXII. — NO. 5. 2 


86 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
PLATE XII. 

Fig. 1. Phrissocystis aculeata A. Ag., apical part of test. 

Fig. 2. Phrissocystis aculeata A. Ag., odd interambulacral area. 

Fig. 8. Phrissocystis aculeata A. Ag., odd ambulacrum. 

Fig. 4. Phrissocystis aculeata A. Ag., left posterior ambulacrum. 

Fig. 5. Phrissocystis aculeata A. Ag., part of left side of test. 

Fig. 6. Phrissocystis aculeata A. Ag., anal system. 

Fig. 7. Phrissocystis aculeata A. Ag., actinal system. 


Figs. 1-7 natural size. 
Fig. 8. Fasciole of Spatagodesma. . 


PLATE XIII. 
Fig. 1. Echinocrepis setigera A. Ag., apical part of test. 
Fig. 2. Echinocrepis setigera A. Ag., odd anterior ambulacrum from above. 
Fig. 8. Echinocrepis setigera A. Ag., odd anterior ambulacrum from below. 
Fig. 4. Echinocrepis setigera A. Ag., posterior interambulacrum from above. . 
Fig. 5. Echinocrepis setigera A. Ag., anal proboscis in profile. 
Fig. 6. Echinocrepis setigera A. Ag., anal system from below. 


All figures natural size. 


PLATE A. 


CHART SHOWING THE TRACK OF THE “ ALBATROSS.” 


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Bulletin of the Museum of Comparative Zoology 
AT HARVARD COLLEGE. 
Vou. XXXII. No. 6. 


THE NERVOUS SYSTEM OF NEREIS VIRENS SARS. 


A STUDY IN COMPARATIVE NEUROLOGY. 


By J. I. HaAMAKER. 


Wirtu Five PLArEs. 


CAMBRIDGE, MASS., U.S. A.: 
PRINTED FOR THE MUSEUM, 
JUNE, 1898. 


Z_ x 


a ee 


= “= 


No. 6.— The Nervous System of Nereis virens Sars. A Study 
in Comparative Neurology. By J. I. HaAmMAKeER.1 


CONTENTS. 

Page Page 
Meroauction ... « « « « . . 89 e. Peripheral Fibres . . . 105 
Methods... ...- «.. . 90|PartIl Dis@ission .... . 106 
eee Description ©. . . « . QOL), 1. Topography. .. ..:°. 106 
aeunoeraphy. . s . . - . SL *'2: Protective Tissue . . .. : 107 
a, Brain: +. « « O23) Brainy «o's sercweostees ASS 
b. Sub-cesophageal eueglion 93| 4. “Mushroom Bodies ” ee es 
ce. Typical Body Segment . 94] 5. Optic Ganglion .... . Ill 
d. Parapodial System. . . 95] 6. Ventral Nerve Cord. . . . 112 
maeerotective Tissue <« <i). . 961) % Centrosomes .. . . .. 112 
oeebrsin’. c « eeraicees? Olt 1S). Nerve HiDreskia wo. ew Lhe 
4. Ciliated Gmnisve sae aness he 100 a: Giant Mibres' < a... IS 
5. Ventral Nerve Cord. . . . 100 b. FibresofSet A... . 115 
Sw Nerve Hibres: «20... ., » 102 c:} Hibresof'Set B : = . . 116 
a Giant Hibres.. 5 . . = 102 d. Fibres of Sev . . . . 118 
ecctiores OF Seb A < 5... 108|Summary .°. 1... . . « +- 8 
ec. Fibres of SetB . . . . 104) Bibliography . . Ses ae 
d. Fibres of SetC . . . . 105! Explanation of Plates rtp 

INTRODUCTION. 


ALTHOUGH so much has been written on the nervous system of repre- 
sentatives of all the chief groups of the metazoa, we are as yet far from 
thoroughly understanding the action of the myo-neural mechanism of 
any animal. It is true, much light has been thrown upon the subject 
during the last decade through the use of the newer methods of investi- 
gation; but the many valuable facts that have been established are as 
yet so disconnected, that they can scarcely be said to be more than sug- 
gestive. In no case has the myo-neural system of an animal been at all 
completely worked out. In the higher animals the complexity of this 
system makes such a task almost impossible. At any rate, the most 

1 Contributions from the Zodlogical Laboratory of the Museum of Comparative 


Zodlogy at Harvard College, under the direction of E. L. Mark, No. XCI. 
VOL, XXXII. — NO. 6. i 


90 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


promising method of approaching the subject would seem to be through 
the simpler forms. Some of the homodynamously segmented animals 
offer advantages in this respect which no other forms do. 

The following considerations may be noted as applying particularly 
to the polychete annelid, N ereis, as a favorable subject for this kind of 
' study :—(1) Nereis has a sharply centralized nervous system, consisting 
of well defined ganglia, which occupy very definite relations to the parts 
they control. (2) The histological elements of the nervous system are 
highly differentiated and constant in their relationships. (3) A typical 
body segment of the animal] is simple in structure, having a compara- 
tively small number of muscles. (4) There is almost no seria] differen- 
tiation of the body segments, excepting in a few of the anterior and the 
anal metameres ; hence it is necessary to determine the structure of one 
segment only in order to know the structure of nearly the whole animal. 
(5) Since there are only a few muscles, the movements of the animal are 
limited in number, and may readily be analyzed and classified. (6) Phy- 
siological experiments may be performed with more than usual facility, 
because the worms are hardy and live well in the aquarium. To these 
considerations may be added the eminently practical one that Nereis 
may be easily obtained in unlimited quantities. With such material 
the problem before us seems to be presented in a comparatively simple 
form. By these considerations I was led to take up the study of the 
nervous system of Nereis. Some of the results obtained are given in 
what follows. 


Methods. 


The material used for intra-vitam staining was the atokal form of 
Nereis virens Sars. It was obtained from the muddy banks of the 
Charles River at a place where the water at low tide contains less than 
0.3% salt. The worms found here may be transferred to fresh water 
without suffering serious injury. For ordinary histological preparations 
both atokal and epitokal forms were used. The latter were obtained 
from the mud flats of Lynn Harbor at the mouth of the Saugus River. 

Before killing, the specimens were narcotized with chloral hydrate or 
alcohol, and the intestine cleaned by forcing a stream of water through 
it. The body was always opened to allow rapid penetration, and some- 
times the intestine was removed. Two methods of fixing and staining 
were employed: either fixing in corrosive sublimate and staining in iron- 
hematoxylin, or fixing and staining by osmic acid. The value of corro- 
sive sublimate as a fixing agent is well known, and I obtained excellent 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 91 


results by fixing ina1l% to 5% solution of acetic acid saturated with 
corrosive sublimate. Preparations fixed in this way were stained on the 
slide with Heidenhain’s iron-hematoxylin. The osmic acid method of 
vom Rath (’95) gives results in many ways equally good, and for some 
purposes, such as tracing nerves, even better than the corrosive and 
iron-hematoxylin method. I found a mixture in the following propor- 
tions of osmic acid, picric acid, acetic acid, and platinic chloride very 
satisfactory : — 


Mamimiseny 272 oh atk ee. we OTD ee 
Picnic acid, sat.aq. Sol, >. . 2 6 «© YOO. 
iPlatinie’chloride, 2%. 2 2» « .) 25 ee, 
PieetioaG Sit ae a A eh i “eve. 


The results obtained are not at all uniform in quality, since the rate of 
precipitation of the osmium by the pyroligneous acid seems to vary. 
The value of successful preparations, however, counterbalances the 
capriciousness of the method. The results obtained by these two 
methods agree in almost every particular, even to the relative intensity 
of the stains in the various tissues. 

For intra-vitam staining the following method proved most success- 
ful. Specimens of Nereis having about seventy segments were injected 
with a concentrated solution of methylen blue in normal salt solution. 
They were then laid, ventral side uppermost, in a moist chamber for 
about two hours, after which the stain began to appear in the sub- 
cesophageal ganglion. From this region the stain gradually penetrated 
caudad, and when it was thought to have reached its optimum, it was 
fixed by Bethe’s (95) ammonium molybdate method. The objects were 
then embedded in paraffine and cut. 


PART I. DESCRIPTION. 


1. TopograpnHy. 


The central nervous system of Nereis virens is well developed. 
Throughout the entire length of the body the ventral nerve cord ex- 
hibits a sharp differentiation of ganglia and longitudinal connectives. 
The ganglia are segmentally arranged and constant in position; the 
nerves are regularly arranged in metameric groups of five pairs each 
(Plate 1, Fig. 8). The ventral cord lies deeper than the hypodermis, 
from which it is partially separated by the circular muscle bundles. 


92 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


The circular muscles do not form a continuous sheet, but consist of 
small bundles which lie partially embedded in the hypodermis. Some 
of these muscles cross the mid-ventral line external to the nerve, thus 
causing a partial separation of cord and hypodermis. Between the 
muscle bundles, however, the neurilemma of the nerve cord is in contact 
with the hypodermis. ‘The brain also lies deeper than the hypodermis, 
from which it is suspended by a narrow membrane lying in the median 
plane. 
a, Brain, 

The form of the brain is roughly that of a trapezoid (Plate 1, Fig. 1, 
ceb.), the anterior pair of eyes marking approximately the extremities of 
the longer one of the parallel sides, while the posterior pair marks the 
limits of the shorter one. The anterior angles of the trapezoid are 
drawn out toward the palps, thus making the anterior margin of the 
brain slightly concave. The dorsal aspect of the brain is broadly cor- 
date, the re-entrant angle being at the anterior side. Fourteen pairs of 
werves arise from the brain by distinct roots. As they are arranged 
symmetrically, it will not be necessary to describe both sides. Beginning 
anteriorly at the median line, and numbering and describing the nerves 
of one side in order, there is first near the median line a group of three 
nerves (I, II, III), which arise near together. 

The first nerve (I) passes forward, then downward, and finally back- 
ward along the dorsal: wall of the proboscis; the second (II) goes 
directly forward to the antenna; the third (III) runs forward along the 
dorsal wall of the head. 

At the anterior lateral angle of the brain there is another group of 
three nerves (IV, V, VJ). The fourth nerve (IV) divides into two 
branches, one going to the ventro-median wall of the palp, the other to 
the dorso-median wall of the same organ. The fifth nerve (V) extends 
ventrally to the proboscis; the sixth (VI) is the large sensory trunk 
of the palp; and the seventh (VII) arises from the brain laterally, 
between the group just described and the anterior eye of the same side; 
it passes forward along the lateral wall of the palp. 

The eighth, ninth, and tenth nerves are the three roots of the cireum- 
cesophageal commissure. They unite in the commissural ganglion, which 
lies a short distance ventral to the anterior eye. The eighth (VIII) is 
a small nerve arising near the seventh, passing out parallel with it, and 
then turning down into the ganglion. The ninth nerve (IX) arises 
laterally from the brain, passes out directly beneath the eye, and then 
bends down to the commissural ganglion. The tenth (X) arises from the 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 93 


ventral edge of the brain immediately ventral to the ninth, and passes 
out directly to the commissural ganglion. 

The eleventh (XI) and twelfth (XII) nerves are the two optic nerves. 
They converge from the eyes toward the centre of the brain. 

The thirteenth (XIII) nerve arises back of the posterior eye, and 
goes directly to the ciliated groove. The fourteenth (XIV) is a rather 
diffuse nervous connection between the brain and the dorsal surface of 
the head. The region innervated lies nearly midway between the pos- 
terior eye and median plane, but slightly nearer the latter. 

Besides these fourteen paired nerves (I-XIV) there is a single median 
nervous connection between the dorsal surface of the head and the 
brain. This is similar to the diffuse fourteenth nerve, but is smaller 
and lies slightly anterior to it. Its position is shown in Figure 1. 

From the commissural ganglion a nerve (a) passes forward to the 
proboscis, where it unites with the fifth nerve of the brain (V) in a 

ganglion. Another nerve (5) passes backward along the side of the 
head. Four or five small connectives, not shown in Figure 1, unite 
the commissural ganglion with the optic ganglion, which lies in con- 
tact with the ventral side of the anterior eye. Lastly, the circum- 
cesophageal commissure passes from the commissural ganglion around the 
cesophagus to the sub-cesophageal ganglion, traversing on its way a 
ganglion which lies beneath the anterior pair of tentacular cirri. From 
this anterior cirrus ganglion two large nerves go each to an anterior 
cirrus, and, from the anterior side of it, a smaller one () to the pro- 
boscis. On its posterior side the anterior cirrus ganglion is connected 
by a small nerve (@) with the posterior cirrus ganglion, which lies 
beneath the posterior pair of tentacular cirri. The latter ganglion gives 
off two large nerves, one to each of the two posterior tentacular cirri, 
and also sends a nerve (¢) backward along the side of the head. The 
posterior cirrus ganglion is connected with the sub-cesophageal ganglion 
by a large nerve trunk (n. pa-coms.), which lies posterior to and parallel 
with the circum-cesophageal commissure. This trunk gives off several 
branches from a region midway between the posterior cirrus ganglion 
and the sub-cesophageal ganglion. 


b. Sub-cesophageal Ganglion. 


The sub-cesophageal ganglion (gn. sb-oe., Fig. 1) lies on the posterior 
boundary of the cephalic segment. It gives off three pairs of nerves 
besides the commissures and the nerves of the posterior cirri, Begin- 


94 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


ning at the median plane, the first pair of nerves (y) goes to the 
cesophagus; they pass forward near the median line, and then bend 
backward to be distributed to the ventral wall of the esophagus. The 
second and third pairs are respectively the commissures and the nerves 
of the posterior cirri; the other two pairs pass out laterally and forward 
to the walls of the cephalic segment. The ganglia of the first three or 
four body segments are displaced backward, as compared with those of 
the typical segment, and are consequently crowded together, thus mak- 
ing them appear as a single ganglion. Each segment in this region 
receives the typical number of nerves, though in regard to size the 
nerves of each segment do not bear quite the same relation one to 
another as they do in a typical segment. 


ec. Typical Body Segment. 


The ganglia of the ventral chain (Plate 1, Fig. 8) are about half as 
long as the segment, and, if the segmentation of the longitudinal mus- ‘1 
culature be taken to indicate the boundaries of the metameres, they lie 
intersegmentally, with at least two thirds their length in the posterior 
segment. The longitudinal connectives are enclosed in a single sheath, 
so that there appears to be but one connective. At the intersegmental 
plane there is a constriction of the investing tissue of the ganglion, but 
this does not extend to.the nervous part. Five larger pairs of nerves 
are given off from each ganglion, and there are, besides, many smaller 
ones, which consist of only a few fibres each. A few of the latter are 
given off ventrally, but most of them pass dorsally from the mid-dorsal 
line of the nerve cord, and probably are distributed chiefly to the 
digestive tube. 

The paired nerves are most conveniently characterized with reference 
to their position in the segment. Beginning at the anterior end, there 
is close behind the intersegmental constriction of the ganglion the first 
segmental nerve (I, Fig. 8). This nerve is rather slender and passes 
out at right angles to the ventral nerve cord. It lies external to the 
longitudinal muscles, and is partly buried in the hypodermis (I’, Fig. 4). 
It may be traced with little change in calibre to the dorsal base of the 
parapodium, where it is lost either in the circular parapodial muscles, 
or in the hypodermal plexus, or most likely in both. 

The second segmental nerve (II) is the largest of the five, and is the 
parapodial trunk. It leaves the segmental ganglion near its posterior 
end and passes diagonally backward across and external to the longi- 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 95 


tudinal muscles to the parapodial ganglion, which lies in the ventral 
base of the parapodium between the longitudinal muscles and the pore 
of the segmental organ. 

The third segmental nerve (ITZ) j is very small. It arises from the 
posterior end of the segmental ganglion and passes diagonally outward 
and backward to the posterior base of the parapodium. Like all the 
paired segmental nerves, it lies embedded in the hypodermis throughout 
its length. Next in size to the parapodial trunk is the fourth nerve 
(IV). It arises from the anterior third of the succeeding ganglion, and 
hence lies in the posterior part of the segment, near the intersegmental 
line, where the longitudinal muscles are attached to the hypodermis. 
It runs parallel with the first nerve (I) of the following segment, but 
continues in a direct course around the body almost to the mid-dorsal 
line. 

The fifth segmental nerve (V) is very slender. It lies close behind 
the fourth nerve, and very near the intersegmental plane. It extends 
as far as the base of the parapodium. 


d. Parapodial System. 


The innervation of the parapodium (Figs. 5, 8) is almost wholly from 
the parapodial ganglion, from which four nerves radiate toward the 
periphery. The most anterior one (1) is very slender and usually passes 
out in front of the pore of the segmental organ. It goes to the retractor 
muscles of the anterior side of the parapodium. The second parapodial 
nerve (2) is comparatively large, and innervates the ventral ramus. 
Near the ganglion it divides into an anterior and a posterior branch. 
The anterior one passes along the anterior wall of the ventral ramus 
to the anterior setigerous lobe. The other runs along the posterior wall 
to the posterior setigerous lobe, giving off a branch to the ventral cirrus 
and another to the inferior ligula of the ventral ramus. 

The third parapodial nerve (3) passes outward and upward on the pos- 
terior wall of the parapodium. About half way up the side of the para- 
podium it gives off a branch to the glandular region of the dorsal base 
of the parapodium. Then other branches are sent to the anterior setige- 
rous lobe of the dorsal ramus, the posterior setigerous lobe, the superior 
ligula, and the dorsal cirrus. 

A fourth parapodial nerve (4) goes to the posterior base of the 
parapodium. 


96 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


2. PROTECTIVE TISSUE. 


The protective tissue of the central. nervous system is of two kinds; 
an outer membrane, the neurilemma, and within this a spongy tissue, 
the neuroglia. The neurilemma is better developed in the anterior than 
in the posterior region of the animal, and better in the older epitokal 
individuals than in the atokal forms. In the cephalic segment it is very 
thick and forms a capsule around the brain (n’lem., Plate 2, Fig. 9), 
and it also envelops the nerves from the brain. A tissue similar in 
texture lines the dorsal wall of the head, there taking the place of a 
basement membrane (Plate 3, Fig. 20). The brain capsule is continuous 
with this lining of the wall of the head along the mid-dorsal line, and 
also around the nervous connections that unite the brain with the poste- 
rior dorsal surface of the head. It likewise serves as a place of attach- 
ment for some of the muscles of the head, as the neurilemma of the 
ventral cord does for some of the diagonal muscles ; but elsewhere the 
capsule is free from the wall of the head, being suspended in the cavity 
of the cephalic lobe. 

The neurilemma of the brain is continuous with that of the ventral 
cord along the circum-cesophageal commissures. Except where it is 
pierced by nerves, the neurilemma of the cord (Plate 2, Fig. 18) forms 
a closed tube, whose walls are thickest at the anterior end. Along its 
dorsal side the wall of the neurilemma tube is continuous with the 
tunica intima of the ventral longitudinal blood-vessel by means of a 
narrow membrane which connects the two tubes throughout their 
entire lengths (Fig. 18). 

In structure the neurilemma is uniformly fibrous ; it does not stain in 
iron-hematoxylin or osmic acid. On the outer surface of the brain cap- 
sule there is a layer of nuclei which may possibly belong to the neuri- 
lemma. I have not clearly seen such nuclei on the neurilemma of the 
ventral cord. The connective tissue of the muscles is continuous with 
the neurilemma in many places, and resembles it in every respect. 

The neuroglia of the brain is a network of delicate fibres with numer- 
ous small elongated nuclei located at the nodes of the network. This 
tissue lines the inner surface of the brain capsule, from which it pene- 
trates into all parts of the brain except the neuropil and the masses of 
small nuclei connected with it. The neuroglia of the ventral cord is like 
that of the brain in texture, and it surrounds and penetrates the nervous 
structures of the cord in the same way as in the brain. The portion 
immediately surrounding the cord, however, is somewhat differentiated 


ee ee oe 


i a a ie A 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 97 


from the more peripheral part (Plate 2, Fig. 18). Its fibres are coarser 
and more compact, and they take a circular direction around the cord. 
Between the successive ganglia the fibres of this inner layer also pass 
in between the three longitudinal connectives. A few neuroglia nuclei 
lie scattered about among the nerve fibres of the cord. 


3. BRAIN. 


The brain of Nereis consists essentially of a central mass of interwoven 
fibres with a few irregular masses of neuropil, and a peripheral layer of 
cells loosely arranged in symmetrical groups. The cells have undergone 
a remarkable degree of differentiation, and the cells in each pair of groups 
have distinct characteristics. There are at least six distinct classes of 
cells ; while a number of the larger cells are arranged symmetrically in 
pairs, each pair having individual peculiarities of form and structure. 
The six classes, however, are not characterized by form and structure 
alone. Indeed, it is the difference in chemical reaction that is most 
distinctive, and calls for more than passing mention. The classes are 
as follows : — 

(1) In front, on each side of the brain, between the anterior median 
and the anterior lateral groups of nerves, there lie two masses of exceed- 
ingly small nuclei (Plate 3, Figs. 21, 24). The larger ventral mass is 
approximately crescentic in a transverse section of the brain with the 
concave side of the crescent lateral and partially embracing a mass of 
neuropil. The smaller, dorsal mass of cells is also crescentic in trans- 
verse section, but with the concave side toward the median plane. This 
crescent also partially embraces a mass of neuropil. In preparations 
stained with osmic acid or iron-hematoxylin the cells of these masses 
show only very faint traces of cell boundaries. The nuclei stain very 
deeply, and always contain a number of granules of various sizes. The 
nuclei are about 6 in diameter and are arranged in rows radiating from 
the neuropil (Fig. 21). They are set very closely in the rows, and are 


often almost in contact. The spaces between the rows are wider toward 


the neuropil, while toward the convex side of the mass the arrangement 
is more compact and the alignment of the nuclei almost disappears. 
The spaces between the rows of nuclei have a fine fibrous appearance, as 
though fibres from the cells passed out to the neuropil. Cells similar to 
these occur in other parts of the brain, e. g. a small group at the posterior 
border of the brain, just median to the root of the nerve which runs to 
the ciliated groove (XIII). Cells slightly larger, but otherwise like 


s 
98 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


these, occur scattered over the dorsal surface of the brain, and a group 
of them lies around the root of the fourteenth nerve (XIV). 

(2) At the posterior lateral border of the brain there is a group of 
spindle-shaped cells, which extends backward and outward along the root 
of the thirteenth nerve (XIII) as far as the point where the nerve 
pierces the capsule (Plate 2, Figs. 9, 15). These cells do not stain very 
deeply, and do not show very sharply defined cell boundaries, although 
the spindle form can be distinctly seen. Similar cells give rise to the 
fibres that form the fourteenth nerve and pass out to the dorsal sur- 
face of the head. 

(3) Along the internal border of the last group there lies a third very 
peculiar class of cells (Figs. 9,12). Unlike those of the two preceding 
classes, the cells of this class have a very definite cell boundary. They 
are comparatively few in number, and are narrowly pear-shaped with the 
process extending toward the centre of the brain. In preparations 
stained to best advantage for other structures these cells are so deeply 
stained that only in a few cases can the nucleus of the cell be seen at all. 
The cell process also stains so deeply that it appears in strong contrast 
with the other fibres. 

(4) In the same transverse section as the last, but nearer the median 
plane, is another group of pear-shaped cells (Figs. 9, 11). These are 
larger and proportionately broader than the last, and stain very differ- 
ently from them. In iron-hematoxylin the cytoplasm does not become 
blue, but takes on a brownish color. Its structure is almost homogene- 
ous excepting an irreguiar network of a few coarse fibres which usually 
centres about the nucleus and does not extend throughout the hody 
of the cell. The processes of these cells also go toward the centre of 
the brain. 

(5) At the side of the brain beneath the nerve of the anterior eye 
there lies a group of cells which seem to have no direct connection with 
the brain except that of being enclosed in the brain capsule. The cells 
are rather large and spherical, and send their processes out along the 
ninth nerve (IX) of the brain toward the commissural ganglion. A few 
of the cells lie scattered along the dorsal side of the ninth nerve, and 
make this group of cells continuous with the group which lies beneath 
the anterior eye, and which we have called the optic ganglion. The cells 
of both groups have the same general appearance (Fig. 19). The eyto- 
plasm presents no special peculiarities. There is no cell membrane and 
the limits of the cell are very indistinct, because there are very few 
granules at the periphery. Each cell is surrounded by neuroglia fibres 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 99 


arranged loosely in concentric layers, The inner fibres seem to be em- 
bedded in the cytoplasm of the cell. 

(6) Although the remaining cells (Figs. 16, 17) present a great vari- 
ety of size, form, and detail of structure, there is a general similarity 
which permits of classing them together as a group distinct from those 
we have described thus far. They have the pear shape and the granu- 
lar cytoplasm which are characteristics of most of the cells of the 
ventral ganglia. But beyond this there is little that is common to 
all the cells of the group. In the posterior half of the brain there are 
several pairs of very large cells which have the characteristics of this 
group, and in addition a very striking one of their own. The nucleus 
lies in the narrow end of the cell, and is surrounded by the granular 
cytoplasm. At the other end of the cell, there is a large vacuolar space 
containing a number of deeply staining bodies of irregular form, em- 
bedded in an indistinct coagulum. Other cells have very finely granular 
substance occupying a similar position, the granules being much 
smaller and staining less deeply than those of the body of the cell. 
In these cases the nucleus shows no signs of degeneration. In some 
cells (Fig. 16) the cortical part of the cytoplasm is penetrated by narrow 
lamella, which, when viewed from the surfaces of the cell, present the 
appearance of a honeycomb structure. 

There is another structure within the brain capsule which is very 
strange, and for which I cannot account. It consists of a considerable 
number of spheroidal cavities (Fig. 10), containing a substance which 
assumes several forms. The cavities are arranged in two symmetrical 
groups, one on each side of the brain (Fig. 9), extending around and 
between the fibres of the fourteenth nerve, and backward and outward 
to the root of the thirteenth nerve. The cavities, which are surrounded 
by neuroglia, vary somewhat in size, the average being about equal to 
that of the average nerve cell of the brain. Each usually contains a 
number of spherical granules, sometimes of nearly uniform size, some- 
times differing much in this respect. They are stained in iron-hema- 
toxylin, but in preparations treated with osmic acid they are yellow. 
Sometimes the cavities are filled with an almost homogeneous substance ; 
at other times, however, the substance only partially fills the cavities, and 
assumes an irregular stellate form, In a few cases there are doubtful 
indications of a nucleus. 

These structures cannot be due to degeneration of nerve cells, because 
they are very regular in the place of their occurrence, and there is no 
indication of degenerated fibre tracts. The contents of the cavities are 


100 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


not fat, for they are not blackened by osmic acid, nor do they seem to 
be pigment, since the granules are comparatively large and at the same 
time quite variable in size. Racowitz (’95) found ameeboid cells de- 
positing pigment in the region of the ciliated groove, but I have no 
reason to think the condition in the present instance is due to the same 
instrumentality. 


4, CILIATED GROOVE. 


The ciliated grooves lie on the posterior margin of the cephalic lobe 
behind the posterior eyes (Plate 3, Fig. 20). A fold of the anterior 
margin of the cephalic segment extends forward a short distance over 
the cephalic lobe, to which it is attached in the median plane, and also 
at a point just lateral to the eyes. On the ventral wall of the pockets 
thus formed there is an elongate eminence or ridge about 0.5 mm. long 
and 0.2 mm. wide, with the long axis transverse to the body. Along 
the crest of this ridge lies the ciliated groove. The ridge is formed by a 
thickening of the non-ciliate hypodermis, the cells of which are very long 
and arranged with their distal ends directed toward the crest of the 
ridge, thus producing in cross section the figure of an inverted V. The 
space between the cells which form the ridge is occupied by the ciliated 
cells. The cuticula over these cells is very thin, and the cilia project 
through it, forming a narrow band along the bottom of the groove. The 
nuclei of the ciliated cells lie much deeper than those of the non-ciliate 
cells on either side of them. The organ is innervated by the nerve 
XIII. There are no glands in the hypodermis of this region, but the 
overhanging fold of the cephalic segment is richly supplied with them. 


5. VENTRAL NERVE Corp. 


The structure of the ventral nerve cord can best be set forth by de- 
scribing transverse and longitudinal sections of it. A transverse section 
between ganglia (Plate 5, Fig. 31) shows that there are three longitu- 
dinal connectives ; two large lateral and symmetrical ones, and a small, 
more dorsal median one. Each connective is enveloped by the fibres of 
the inner layer of neuroglia, which thus separates the three connectives. 
In preparations successfully fixed in either the corrosive sublimate or 
osmic acid mixtures, the cross section of the connectives shows nothing 
but the circular outlines of the cut nerve fibres, with their contents and 
a few neuroglia fibres penetrating the connective from the sides. The 
fibres vary greatly in size, from the large giant fibres, which are one 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 101 


third the diameter of a lateral connective, to the smallest, which how- 
ever are large enough to enable one to distinguish the circular outline of 
the sheath and its contents. 

There are three giant fibres, one in each connective. Those in the 
lateral connectives are much larger than the median one. 

On the median side of each of the paired connectives, close beneath 
the median connective, there is another very large fibre which, in some 
regions of the body, is but little smaller than the median giant fibre 
(Plate 5, Fig. 31). These fibres, which I shall call set A, also stain very 
lightly, but they show no traces of a network. 

The numerous fibres which constitute the remaining portions of the 
connectives stain more deeply. Most of them show no differentiation, 
but frequently the larger ones are more intensely stained in the centre 
than at the periphery. 

In longitudinal sections of the connectives (Plate 3, Fig. 26), the 
fibres appear as parallel bands separated by crinkled lines, — the fibre 
sheaths folded by a slight longitudinal contraction of the animal at the 
time of fixation. Many of the larger fibres, excepting set A, often show 
a darker central band corresponding to the darker centre of the trans- 
verse section. A few nuclei are scattered among the fibres of the 
connectives. 

Transverse sections through the ganglia of the ventral chain present a 
single central filrous mass bordered ventrally and laterally by ganglionic 
cells. Bundles of neuroglia fibres pierce the central mass at intervals 
along the median plane, and divide the ganglion into symmetrical halves. 
The greater part of the fibrous mass consists of longitudinal fibres, but 
there are many fibres which traverse the ganglion in other directions. 

The cells of the ventral ganglia do not vary as much in size, form, and 
structure as do those of the brain ; however, besides the uniformly gran- 
ular ones of various sizes and shapes (Plate 2, Figs. 13, 14, A), corre- 
sponding to those of class six in the brain, there are some cells (Fig. 
14, B) which stain very lightly, and the cytoplasm of which is homo- 
geneous with the exception of a few coarse granules of very limited dis- 
tribution. There are only a few pairs of these cells in each ganglion ; 
one of the pairs belongs to the fibres of set A, and these are among the 
larger cells of the ganglion. 

The coarse irregular granules of the cells last described occupy the 
middle of the cell, where they are arranged in the form of a hollow 
sphere, at the centre of which there is a round deeply staining granule 
(Fig. 14, B). This structure is undoubtedly what has been described as 


102 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


a centrosome. It is not confined to this class of cells, but in good prep- 
arations occurs with such frequency that it may be said to exist in all 
the cells of the ventral cord (Fig. 13). The nucleus is always eccen- 
tric, and frequently, though not always, flattened. There are often two, 
three, or more centrosomes in a single cell. In one instance there were 
ten. In the cells whose cytoplasm is granular the centrosome does not 
appear as distinctly as it does in the others. However, when the stain- 
ing has been successful, there appears at the centre of the cell a mass of 
granules which are larger and stain more deeply than those of the rest 
of the cell. The granules of this mass are arranged in the form of hol- 
low spheres, the contents of which are destitute of all granules excepting 
the single round body at the centre. 


6. NeERvE FIBREs. 


a. Giant Fibres. 


There are three giant fibres which traverse the ventral cord through- 
out its entire length (Plate 2, Fig. 18, Plate 5, Fig. 31) ; the pair of 
extremely large ones, which lie one on the outer side of each of the 
paired connectives, and the smaller unpaired one lying in the median 
connective. All these have the same peculiarities of structure. With 
the methods employed they stain very lightly and appear almost homo- 
geneous. On close examination, however, the section of the fibre is seen 
to be made up of a small number of polygonal areas marked off by an 
indistinct network (Plate 1, Fig. 3). This network apparently owes its 
existence simply to the presence of discrete masses of protoplasm, the 
boundaries of which give the appearance of a network. In longitudinal 
sections the giant fibres show the same structure, except that the polygo- 
nal areas are elongated in the direction of the axis of the fibre. When 
these fibres are stained in methylen blue, the stain is precipitated at the 
borders of the areas, producing a finely granular network in a homoge- 
neous field of blue. 

The paired fibres may be traced forward into the circum-cesophageal 
connectives to a point between the anterior cirrus ganglion and the 
commissural ganglion, where they divide into a number of small branches. 
The branches cannot be distinguished from other large fibres of the con- 
nective, but they appear to pass through the commissural ganglion to 
the optic ganglion. The fibres which connect the commissural and optic 
ganglia are processes of the cells of the optic ganglion, but since I was 
unable to trace a fibre continuously from the optic ganglion until it 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 103 


united with the giant fibre, I cannot be sure that there is such a con- 
nection. I have found no other cells connected with these giant fibres, 

The median giant fibre divides in the sub-cesophageal ganglion into 
several branches, which continue forward parallel with one another along 
the median plane. One of them I was able to trace to one of a group of 
large cells lying between the ventral ends of the cirecum-cesophageal con- 
nectives. The other cells of the group are connected with similar fibres, 
but I could trace only one continuously from the cell to the giant fibre. 

The three giant fibres extend back into the last segment of the body 
without branching or changing their relative sizes or positions. Occa- 
sionally the median fibre in passing through a ganglion divides and 
allows the passage of a bundle of fibres between the two parts, which 
then immediately reunite, and the fibre continues on as before. This 
condition occurs frequently, but appears to be wholly accidental, since it 
is very irregular in the frequency of its occurrence, as well as in the size 
of the loop produced, and also in the relative sizes of the two divisions 
of the fibre. In one instance I found a similar condition in one of the 
lateral giant fibres, but it was not very well marked. 

The giant fibres are pierced by many smaller ones, which pass directly 
through them (Plate 1, Fig. 2). In the case of the lateral giant fibres 
this occurs most frequently near the places where the segmental nerves 
are given off from the ganglion. Sometimes the small fibres branch 
within the large one, the branches then continuing on through the giant 
fibre. In preparations stained with osmic acid, the small fibres stain 
much more deeply than the giant fibres, thus becoming very distinct. 
In a part of a methylen blue preparation which had not taken the stain, 
the small fibres traversing the giant fibres could be readily seen because 
they were more highly refractive than the giant fibre. 

I cannot say that in successive segments the giant fibres are pierced 
by corresponding sets of smaller fibres, but there is at least one set 
which regularly traverses the giant fibre on passing out into the fourth 
(IV) and fifth (V) segmental nerves. This fibre will be described as 
set B, 

b, Fibres of Set A. 

Along the inner margin of the lateral connectives there lies a set of 
fibres (Plate 2, Fig. 18, Plate 5, Fig. 31) which in transverse section 
are almost as large as the median giant fibre, and resemble it in their 
resistance to stains. They differ from giant fibres, however, in the fol- 
lowing particulars (compare Plate 4, Fig. 27, 4):—(1) They are ar- 
ranged segmentally, one pair of fibres originating in each segment ; 

VOL. XXXII. — No. 6. 2 


. 


104 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


(2) Each fibre is connected with a single cell; (3) They do not extend 
through more than two segments; (4) They are not pierced by other 
fibres, nor (5) do they show the reticulum found in giant fibres; (6) They 
are branched. The cell (Plate 4, Fig. 27) of which this fibre is a process 
lies on the ventral side of the ganglion near the origin of the third seg- 
mental nerve (III). The general direction of the process is forward, but 
at the outset it crosses and recrosses the median plane, decussating twice 
with its companion of the other side, one decussation being immediately 
behind and the other in front of the origin of the second (II) segmental 
nerve. After the second crossing the two fibres run side by side close 
beneath the median giant fibre, until they pass the first point of decus- 
sation of a similar set of fibres in the next anterior segment. Here they 
diverge and apparently break up into fibrillations or branches too small 
to be traced in preparations stained in the ordinary way. I have not 
succeeded in staining this fibre with methylen blue. This system is well 
developed in every segment from the last one of the tail to within twenty 
segments of the head, where the fibre gradually becomes smaller until, 
in the first three or four segments, it cannot be distinguished among 
the other fibres of the cord. 


ce. Fibres of Set B. 


Next in size come the cells and fibres of set B (Plate 4, Figs. 27, B, 
28). The cells lie ventrally about midway between the origin of the 
first (I) and second (II) segmental nerves. From each cell a process 
extends forward and gradually rises into the middle of the ganglion. 
Opposite the origin of the fourth (IV) segmental nerve, the fibre turns 
squarely across the ganglion, running parallel to its mate, with which 
it decussates, and then divides into two branches, both of which go to 
‘the periphery ; one through the fourth (IV), the other through the fifth 
(V) segmental nerve. The two fibres of a pair lie in contact for some 
distance where they cross from one side of the ganglion to the other 
(Plate 1, Figs. 6, 7), and they anastomose at several points along the 
line of contact (Plate 4, Fig. 28). The fibres of sets A and B are in- 
timately associated at the point where they cross each other (Plate 1, 
Fig. 6, Plate 3, Figs. 22, 23), for they are not only in contact, but the 
smaller fibres lie in a deep indentation on the larger one. The relation 
of fibre B to the lateral giant fibre is still more intimate. Immediately 
after branching, one or both branches pass directly through the lateral 
giant fibre before passing out of the ganglion (Plate 1, Fig. 2). Some- 
times one branch may pass around the giant fibre, but still be in con- 


ee ee 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 105 


tact with it, while the other branch passes directly through it. Some- 
times the penetrating branch, instead of passing through the middle of 
the giant fibre, goes so far to one side that it does not become free from 
the sheath of the giant fibre, but is still wholly embedded in its 
substance. 

d. Fibres of Set C. 


The next fibre system (Plate 4, Figs. 27, 30), set OC, is apparently 
centripetal, since no cell was found connected with it, and since what ap- 
pears to be the main fibre, entering the cord from the fourth segmental 
nerve (IV), immediately divides, forming the characteristic Y of centrip- 
etal fibres. One of the branches runs directly back and ends in fibrillations 
opposite the second nerve (II) of the succeeding segment. The other 
branch runs forward, and ends in a similar way opposite the second seg- 
mental nerve (II) of its own segment. Near its origin the second 
branch gives off a third which runs diagonally backward and across the 
ganglion, ending in a position symmetrical to the ending of the first 
branch. Since the counterpart of each of these three branches is found 
on the opposite side of the nerve cord, there must be six branches ending 
in each segment, on either side three, all of which are opposite the sec- 
ond segmental nerve (Fig. 27, II). The ends of the fibres are enlarged, 
and give off a few fibrillations. The three endings of each side of the 
body lie side by side, and are connected with one another by several 
ladder-like anastomoses (Plate 4, Figs. 29, 30). The fibres of this set 
are rather large, and lie almost wholly. on the ventral side of the cord. 
The third or decussating branches, however, are rather slender, and in 
erossing the ganglion first curve up and then down. Where the two 
fibres eross each other they are always in contact. 


e. Peripheral Fibres. 


The following are some of the fibres found in the parapodial ganglion 
(compare Plate 1, Figs. 5, 8, Plate 5, Fig. 39): (a) Fibres entering the 
ganglion from the second (II, Figs. 5, 39) segmental nerve pass through 
the ganglion and out either by the first (1) or by the fourth (4) para- 
podial nerves. (0) Fibres entering from the segmental nerve divide 
into two branches, one of which passes out through the second (2), the 
other through the third (3) parapodial nerve. Neither of these classes 
of fibres gives off fibrillations in the ganglion. (¢) A third kind of fibse 
enters the parapodial ganglion from the segmental nerve, and ends in 
the ganglion in fibrillations. 


106 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


The second (2) and third (3) parapodial nerves contain both motor 
and sensory fibres. In Figure 32 the motor fibres are shown, and in 
Figure 33 the sensory fibres of the third parapodial nerve. The motor 
fibres turn back along the muscles that move the sete, and are lost 
among the muscle fibres. The cells of the sensory fibres lie far beneath 
the hypodermis. They send a process either to the hypodermis, or to 
the tissue around the openings through which the setz project. At the 
latter place the fibres apparently end in fibrillations. Figure 37 repre- 
sents a sensory cell of the anterior wall of the parapodium. The periph- 
eral process of this cell enlarges just beneath the cuticula into a small 
knob, from which a fine prolongation extends out through the cuticula 
Figure 38 represents a similar cell and nervous process in the posterior 
wall of the parapodium. In Figure 35 is seen a sensory cell from the 
base of the parapodium, and in Figure 36 one from the side of the body 
near the fourth segmental nerve. 

Figure 34 shows the manner in which the motor fibres end in the 
longitudinal muscles, and Figure 40 shows the bushy endings of the 
fibres around the glands of the hypodermis between the bundles of 
circular muscles. 


PART II. DISCUSSION. 


1. TopoGRAPHy. 


In methylen blue preparations it is usually not easy to determine the 
relation of the stained fibres to other organs, because of the difficulty of 
seeing structures which are not stained. For this reason I first made 
a study of the topography of the nervous system, tracing the nerves 
with considerable detail in preparations made by vom Rath’s method. 
3y this means nerves consisting of but afew fibres can be traced through 
serial sections. The account of the topography given in Part I. is 
more minute, but otherwise agrees in the main with that given by 
Quatrefages (50) for Nereis. There is one important point, however, 
in which I cannot agree with Quatrefages, He states that the segmen- 
tal nerve which he designates by the letter o (Planche 3) passes forward 
through the dissepiment to the preceding segment, thus making a ner- 
vous connection between two segments, in addition to that of the ventral 
nerve cord. From the diagram (Plate 1, Fig. 8) it will be seen that there 
is no segmental nerve passing from one segment to another in N. 
virens. ‘The three nerves (I, IV, V) that arise near the intersegmental 
plane pass out parallel with that plane, two anterior to it and one 


i> 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 107 


posterior. The segmentation of the longitudinal muscles is marked by 
an interdigitation of the fibres of one segment with those of the next. 
These interdigitations lie in the plane of the constriction of the body 
which gives the external appearance of segmentation. The line of 
attachment of the longitudinal muscles to the hypodermis (Plate 1, 
Fig. 4) and the constriction in the protective tissue of the segmental 
ganglion (Plate 1, Fig. 8) also lie in this plane, which, as will be seen 
from Figures 4 and 8, thus separates the fifth (V’) and first (1’) seg- 
mental nerves throughout their length. The segmental dissepiment is 
concave anteriorly. Its ventral median edge is attached in the con- 
striction of the segmental ganglion, and is therefore in the intersegmental 
plane. But its lateral border is attached to the hypodermis, between 
the dorsal and ventral longitudinal muscles, anterior to the interseg- 
mental plane and even anterior to the position of the fourth (IV’) seg- 
mental nerve in that region (Fig. 4). Hence, if the position of the 
dissepiment were taken to determine the boundary of segments, the 
fourth (IV’) and fifth (V’) segmental nerves would appear to pass 
backward from the segment in which they arise to the one succeeding it. 
But I have found no segmental nerve passing forward through the 
dissepiment as described by Quatrefages, nor indeed passing out of the 
segment in either direction, if we determine the boundary of segments 
by the segmentation of the musculature. 

When compared with other annelids, we find that Nereis presents a 
generalized condition with respect to its nervous system. It indeed agrees 
very well with the description given by Lang (’88-’94) of the nervous 
system typical of Chetopods. In comparison with other Polychetes, 
however, Nereis shows a rather high degree of development, indicated 
by the deep position and elaborate protective tissue of the ventral nerve 
cord. In the majority of Polychetes the ventral nervous system lies 
embedded in the hypodermis, or intimately connected with it. In a 
few genera, however, such is not the case. Wawrzik (’92) shows that in 
Hermione and Aphrodite the ventral cord is entirely free from the hy- 
podermis, and in this respect he classes these genera with the Oligo- 
chetes. Nereis would also belong to this class, since the ventral cord 
lies internal to the circular muscles, as it does in the Oligochetes. 


2. PRorectivE Tissue. 
The nature and origin of the protective envelopes of the nervous sys- 
tem of Polychetes have been the subject of considerable discussion. 
The differences of opinion are probably due chiefly to real differences in 


108 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


the animals studied. There is not much doubt, however, concern- 
ing the origin of the inner spongy layer, the neuroglia. Jourdan (’84) 
showed that the enveloping tissue of the central nervous system was 
intimately connected with the cells of the hypodermis. Rohde (’87) 
called this tissue “ Subcuticularfasergewebe,” and described it as a 
development of the basal processes of the cells of the hypodermis. 
Wawrzik (’92) made a comparison of a large number of Polycheetes, and 
found that in all those in which the ventral cord was connected with 
the hypodermis the neuroglia was an integral part of the hypodermis 
cells. Haller (’89) denies the existence of the condition described by 
Rohde (’87) for Polynoé, since he found that the nerve cord was sur- 
rounded by a membrane which separated the neuroglia from the hypo- 
dermis. However it may be in this case, there certainly cannot be a 
connection between the hypodermis and neuroglia in such forms as 
Hermione, Aphrodite, and Nereis, in which these structures are clearly 
separated. But the condition found in so many other genera indicates 
that the neuroglia is derived from the ectoderm along with the nervous 
elements. 

The neurilemma is apparently found only in those forms in which 
the nerve cord is free from the hypodermis. But even when present it 
may be so thin as to be readily overlooked. Such is sometimes the case 
at the posterior end of Nereis, On the other hand, it becomes very 
thick around the brain of Nereis, sometimes reaching a thickness of 
fully 100u. Friedlander (’88) and Graber (’80) call this structure 
cuticular. Haller considers it simply the matted fibres of the neuroglia. 
Racowitza (96) states that muscle fibres, as well as the neuroglia, con- 
tribute to make up the neurilemma. Where muscle fibres are attached 
to the outer surface of the neurilemma, or neuroglia fibres to its inner 
surface, membrane and fibre shade insensibly into each other, so as to 
suggest their structural identity. But, as has been shown above, as 
well as by other writers, the neurilemma in its reaction to stains is 
very different from either muscle or neuroglia. Whatever may be the 
weight of this evidence, it is clear that the neurilemma, the connective 
tissue of the muscles, and the tunica intima of the ventral longitudinal 
blood-vessel have the same structure, and must be derived from the 
same source. That source is most likely the mesoderm. 


3. BRAIN, 


Although the brain of Nereis gives rise to so many nerves, it is 
small and simple when compared with the brain, for example, of the 


Se i be es 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 109 


decapod Crustacea. In the latter, the fibrous part is relatively much 
greater, and the fibres are collected into small bundles forming numerous 
commissures between the various parts of the brain. Since the number 
and size of the nerves leaving the brain of decapod Crustacea is small 
compared with the size of the brain, the increase in the fibrous sub- 
stance of the brain must be due to a greater development of the associa- 
tion fibres of all kinds, including not only fibres which lie wholly within 
the brain, but also those branches of centripetal and centrifugal fibres 
which bring the various parts of the brain into relation with one another. 
This condition is apparently correlated with the increased development 
of the “ mushroom bodies” in Arthropods, as we shall see below. 


4, “ MusHroom Bopigs.” 


The compact masses of small nuclei that lie in the anterior part of 
the brain of Nereis (Plate 3, Figs. 24, 21) have been described by a 
number of writers, who have, however, usually expressed considerable 
doubt concerning their significance. Ehlers (’68) and Schréder (’86) 
describe this structure under the name “ Nervenkérner.” Rohde (’87) 
calls a similar structure in Polynoé and other Polychetes ‘ Nerven- 
kernen.” Retzius (’95) refers to it as a “ Haufen groben Korner,” 
which he says are larger about the periphery of the mass. He thinks 
the larger granules may be cells, but doubts the cellular character of 
the smaller ones. His preparations were stained in methylen blue, but 
showed no processes connected with the nuclei. Haller (’89) discusses 
the nature of these structures at some length, and describes the elements 
as small multipolar ganglion cells. He calls the mass a “ Tentakel- 
ganglion,” and supposes it to be connected with the sense organs of the 
antenne. Racowitza (’96) applies to it a similar term, “ganglion anten- 
naire,” but he does not mean to indicate thereby that the ganglion has 
any direct connection with the antenna. Haller objects to Rohde’s ap- 
plication of the descriptive term ‘‘ Hutpilz ” to these ganglia “ weil sie 
sehr leicht zu einer Verwechselung mit den hutpilzférmigen K6érpern 
am Hirn der Insecten veranlassen diirfte, mit denen aber diese Ganglien 
nichts Homologes aufweisen kiénnen.” 

Notwithstanding this statement of Haller, I think there are good 
reasons for considering this organ as in some degree homologous with 
the mushroom bodies of the insect brain. The resemblance between the 
two appears more strongly, if we compare both with a corresponding 
structure in the brain of the crayfish. On the anterior lateral border 
of the brain of this Crustacean there is a triangular mass of small cells 


110 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


which Krieger (’79) designates as gz;. In my own preparations of the 
brain of the crayfish I find that this ganglion resembles the “ ganglion 
antennaire” of Annelids in the following points. In both, (1) such 
ganglia are confined to the brain, no similar structure occurring in the 
ventral cord. (2) The ganglion is intimately associated with the masses 
of neuropil, which also occur nowhere but in the brain. (3) The small 
size of the nuclei and the meagre cytoplasm distinguish these cells 
from the other cells of the brain. (4) There is a peculiar arrangement 
of the cells in rows radiating from the neuropil. According to the de- 
scription given by Kenyon (’96), the mushroom bodies of the honey bee 
exhibit the same peculiarities. The chief difference to be found in the 
three cases is the relative size of the nuclear and the neuropil masses, 
and in the arrangement of the two parts. In Nereis the nuclear mass 
partially surrounds the neuropil, whereas in the insect the relation of 
the two parts is reversed, the neuropil partly enveloping the nuclear 
mass. The crayfish presents an intermediate condition in this respect, 
The nuclear elements do not stain readily in methylen blue, —a condi- 
tion also found by Allen and Bethe in Crustacea, and by Retzius in 
Nereis ; but in the bee Kenyon obtained impregnations of the cells by 
the Golgi method. His preparations show that the cells of these ganglia 
send processes into the neuroglia, where they end in dendrites almost as 
complex as those found in the brain of Vertebrates. Since in the worm 
there is relatively little neuropil, the dendrites of the associated cells 
will probably be found to be less well developed. Kenyon’s supposition 
that the intelligence of the insect is to be accounted for by the com- 
plexity of the relations between the nervous elements made possible by 
these association fibres seems quite plausible ; and if we apply the 
same argument to the worm, we may suppose its low intelligence to be 
in part correlated with the small amount of neuropil, or, in other words, 
the limited development of the association fibres. 

Aside from the cells of this ganglion and those connected with the 
ciliated groove, the brain of Nereis contains about as many cells as a 
typical ganglion of the ventral chain. If we compare the brain with 
the ganglia of the ventral chain, or if we compare the central nervous 
system of Annelids with that of Arthropods, the only structural condi- 
tion to be found which warrants the supposition that it is correlated 
with the supposed psychic functions of the brain is the mushroom body 
and the related development of association fibres. This correlation has 
often been pointed out for insects, and I think we may extend the ob- 
servation to decapod Crustacea and Annelids. 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. y ig bi! 


Racowitza shows that those Polychetes which lack antennz also lack 
the “ ganglion antennaire.” He does not prove, however, that the cells 
of this ganglion may not be present in the brain, and therefore does not 
exclude the possibility that the ganglion may be present in a diffuse 
form. 


5. Optic GANGLION. 


The condition of the optic ganglion in Nereis virens is of interest, 
because it serves to explain what have hitherto appeared to be unac- 
countable differences between several species of Nereis. Carriere (’85, 
pp. 33-35) described this ganglion for N. cultrifera, and Retzius (’95) 
found it in N. diversicolor. On the other hand, Carriére says there is 
no such ganglion in a species from Norderney which he examined, and 
Graber (’80) and Haller (’89) also failed to find it in Nereis coste. It 
seemed strange that a central ganglion, like this, should exhibit such 
will-of-the-wisp peculiarities in passing from one species to another so 
closely related to it. I think, however, that the condition of this gan- 
glion in N. virens shows clearly what becomes of the ganglion when it 
disappears from its place beneath the anterior eye, as in N. costa. In 
N. virens the ganglion evidently lies partly beneath the eye and partly 
within the brain capsule. A few scattering cells show the path the gan- 
glion has taken in its migration inward or outward. It is not only the 
great similarity in the appearance of the cells and the contiguity of the 
two parts that makes this view seem probable, but also the cells of both 
groups send their processes to the commissural ganglion and neither part 
appears to be directly connected with the brain. It is not apparent what 
is the relation of the ganglion to the anterior eye. Carriere thought 
the ganglion formed part of the connection between the eye and the 
brain, but this cannot be, for later writers agree that the anterior eye 
as well as the posterior is innervated directly from the brain. 


The posterior end of the brain deserves more careful study than I 
have as yet been able to give it; I shall therefore simply call attention 
to a few facts. Five of the six kinds of cells described for the brain are 
to be found in the posterior part, and of these five three are not found 
elsewhere. Moreover these three are the most peculiar ones, — those of 
the second, third, and fourth classes. This portion of the brain is partly 
separated from the remainder of it, and is intimately connected with 
the surface at the ciliated grooves and at the dorsal sensory regions 
through the thirteenth (XIII) and fourteenth (XIV) nerves. Perhaps 


112 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


the whole is to be considered a complex sensory organ, analogous to the 
olfactory organ of Vertebrates in its intimate relation with the brain. 
Retzius shows that the sensory fibres of the ciliated groove are processes 
from bipolar cells of this region. The fibres of the fourteenth pair of 
nerves are the processes of cells similar in form and position to the 
bipolar cells of the thirteenth nerve. 


6. VENTRAL NERVE Corp. 


The structure of the ventral nerve cord has been well described for 
Lumbricus by Friedlander (’94), and Hatschek (89-91) has given a 
good figure of a transverse section of the ventral cord of Sigalion. Most 
writers, however, have not succeeded in preparing the ventral cord so as 
to show clearly that the connectives consist wholly of longitudinal fibres. 
There is nowhere in the ventral cord a neuropil in the sense of that 
which is found in the brain. There are small masses of fibrillations in 
the ganglia, of course, but they simply fill up the interstices between the 
fibres, and never occur in masses large enough to produce the punctate 
appearance peculiar to the neuropil of the brain. 

The paucity of nuclei among the fibres of the cord will not permit one 
to regard the fibre sheaths as composed of the expansions of non-nervous 
cells. In the decapod Crustacea the fibre sheaths are nucleate, and in 
the case of the sheath of giant fibres the nuclei are so numerous that 
the sheath may be described as a flat endothelium. In Nereis, however, 
the sheath must be a product of the fibre itself. 


7. CENTROSOMES. 


Since Lenhossék (’95) announced the discovery of the centrosome in 
the adult nerve cells of the frog, there have appeared a number of papers 
describing similar structures in Reptiles (Buehler, 795), Cyclostomes 
(Schaffer, 96), Molluscs (McClure, ’96), and Worms (Lewis, ’96). Hei- 
denhain (’97) summarizes the evidence and gives a bibliography. Dahl- 
gren (97) describes what he calls a centrosome artifact in the spinal 
ganglia of the dog. This artifact, he says, is produced by the formation 
of a crystal of corrosive sublimate in the cell. In Nereis I find the 
best demonstrations of centrosomes in preparations that have been fixed 
in corrosive sublimate, but they also occur in preparations fixed in the 
osmic acid mixture of vom Rath. I think there is no reason for con- 
sidering the phenomenon an artifact in this case. I will simply call 
attention in this connection to two facts that were mentioned previously ; 


ig i i i i 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 113 


first, the general occurrence of the centrosome in the cells of the ventral 
ganglia, and, secondly, the large number of centrosomes that may occur 
in a single cell. I have no explanation to offer for the latter condition. 
Since the structures appear only under special conditions of staining, 
and since I had only one preparation of the brain stained in iron-hzma- 
toxylin, I am not in a position to say whether the centrosome occurs in 
the brain or not, even though I failed to find it in the preparations 
I had at hand. 


8. Nerve FIpres. 


a. Giant Fibres. 


The literature concerning giant fibres is voluminous, and extensive 
bibliographies on the subject may be found in the works of Eisig (’87) 
and Friedlander (’88, 94). I shall concern myself here with only a few 
of the many points in which these fibres have given rise to discussion. 
It has been frequently demonstrated that they are the processes of cells, 
and they have been taken by many writers to be nervous in function, 
but some authors still doubt that that is their nature ; Lenhossék (’92), 
for example, has recently expressed the conviction that they are not. 
The most serious objection that has been urged against their nervous 
nature is the absence of evidence that they are related to other ner- 
vous structures, either by fibrillations within the cord or by centrifugal 
branches. 

I think there is sufficient reason for maintaining that in Nereis virens 
the fibres of set B& serve as branches for the lateral giant fibres. I 
therefore believe that the function of the latter is to transmit nervous 
impulses like ordinary nerve fibres. 

The most peculiar feature of giant fibres is that they are often con- 
nected with more than one cell. In 1881, Spengel (’81) arrived at the 
conclusion that in Halla there was a fusion of giant fibres, but he bad 
no direct evidence. Rohde (’87), however, shows conclusively that at 
least one giant fibre in the ventral cord of Sthenelais is formed by the 
union of the processes of two cells. These lie in the brain and send 
their processes through the circum-csophageal connectives to the sub- 
cesophageal ganglion, where they fuse and whence they continue as a 
single fibre throughout the entire length of the animal. Friedliinder 
(88) found that the lateral giant fibres of the earthworm are connected 
with a number of cells in the posterior segments of the animal. This 
discovery was confirmed by Cerfontaine (’92), who also found that the 
median fibre is connected with several cells at the anterior end of the 


114 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


body. In Rhynchelmis, too, according to Vejdovsky (88, ’92), the giant 
fibres are connected with a number of cells and in such a way that 
each might well be considered a bundle of fibres. Finally, Lewis (96) 
describes in a Moldanid a giant fibre which is connected with a large 
number of cells. There is not yet sufficient evidence to show whether 
the giant fibres of Cheetopods are more frequently multicellular or uni- 
cellular, but there can be no doubt that they are often multicellular. 

The giant fibres of Crustacea have not been so well investigated as 
those of Chzetopoda, but in Homarus, at least, each giant fibre is the 
process of a single large céll, according to the description of Allen (’94). 

Our present knowledge of the giant fibres (in the sense in which I use 
the term) might be summarized in the following way. The giant fibres 
of Annelids and Crustacea are much larger than ordinary fibres, and ex- 
tend for long distances through the central nerve cord ; they are con- 
nected either with one very large cell or with the processes of several 
cells, and they give off neither fibrillations nor branches. In some cases, 
as in Lumbricus, there are anastomosing bars, or connections, between 
two giant fibres; in others, the giant fibres may divide or they may fuse 
with one another, but in no case is there an ending corresponding to the 
fibrillations of other nerve fibres by which the giant fibres might be put 
in connection with other nervous structures. In Nereis, however, there 
is a very intimate connection between the lateral giant fibres and the 
centrifugal branches of set B, as I have shown, and by this system of 
connections the giant fibres are put in relation with every segment of the 
body. 

What the function of such giant fibres may be is readily conceivable, 
and I believe the true explanation has already been offered by several 
writers. Vignal (’83) suggested that their purpose was to bring about 
a more direct connection of the nervous system as a whole than is done 
by less extensive fibres. Friedlander’s experiments on the earthworm 
show that, when the ventral cord is severed, the sudden longitudinal 
contraction of the body can no longer be brought about. Friedlander 
argues that, since these fibres are the only ones, so far as we know, that 
pass through the entire length of the animal, it is reasonable to suppose 
they are the ones that conduct the stimulus for this contraction. 

In Nereis I have frequently noted a sudden longitudinal contraction 
where there was apparently no stimulus except the passing of a shadow. 
I have. not yet had the opportunity to test this further, to determine if 
the stimulus proceeded from the eyes, but I found that no tactile stim- 
ulus was sufficient to produce such a sudden and general longitudinal 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. I i 7) 


contraction. When the habits of the animal are considered, it is pos- 
sible to understand what the function of such a contraction brought 
about by the stimulus of light might be. The worm lives in the mud 
in burrows, and frequently rests with the anterior end above the surface, 
while the remainder of the body is in the burrow. Under such circum- 
stances the longitudinal contraction would cause the animal to retreat 
into the burrow, for longitudinal contractions are in general accompanied 
by the pointing of all the parapodia towards that end of the body from 
which the stimulus comes. For example, if the stimulus is applied at 
the anterior end, the parapodia are all thrown forward, and the longitu- 
dinal contraction of the body immediately follows. This will cause the 
anterior end to move towards the tail while the latter remains station- 
ary, since the position of the parapodia prevents movement of the body 
in the opposite direction. Now, if the shadow cast by a predatory 
animal were to bring about this movement, the mechanism would be of 
vital importance to the worm. Perhaps the importance of the function 
and the great extent of the movement brought about help to account 
for the large development of the giant fibres. The objection may be 
urged that since the phenomena which I have described for Nereis have 
not been found elsewhere, they cannot be of general importance, even if 
the condition be admitted for Nereis. But the exceptional conditions 
under which such phenomena can be observed render it probable that 
they may have been overlooked even when present. 

It must be remembered that, in order to demonstrate the passage of 
one fibre through another, there must be a differential staining of the 
substance of the two fibres. Only in preparations fixed and stained by 
the method of vom Rath, and not in all of these, have I obtained such a 
differentiation. Successful preparations, however, leave no doubt con- 
cerning the actual relation of the fibres, for I have carefully compared 
series of sections cut in each of the three cardinal planes, and always 
with the same result. 

If, then, the giant fibres are nervous in function, the neuron theory 
of Waldeyer (’91) will require considerable modification. The nervous 
element is not always unicellular, but may consist of a number of cells 
united in function, The nervous connection between fibres is not always 
through fibrillations; it may be directly between the axis cylinders 
themselves. 


b, Fibres of Set A. 


Since little is known about the relations of the fibres of set A to other 
fibres, we cannot say much about their probable function. Nevertheless, 


116 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


there are several facts which point to a connection with the forward 
locomotion of the animal. The worm advances by a rhythmical move- 
ment of the parapodia, which begins at the posterior end and passes 
toward the head. With this movement there is usually associated a 
serpentine motion of the body, which also passes from behind forward, 
Both movements are less vigorous near the head, and the serpentine dis- 
appears entirely between the twentieth and tenth segments. The size 
of the fibres of set A in a given region corresponds to the degree of 
activity of the locomotor movements of that region. Whether this 
fact is more than a mere coincidence I cannot say, but it would seem 
to be so. Besides, if there is a causal relation between the condition of 
these fibres and the locomotor movements, we may even account for the 
enormous size of the fibres on the ground of their functional importance. 
Another evidence of this correlation is the serial arrangement of the 
fibres, which may be connected with the progressive character of the 
motor excitation, and with the postero-anterior disposition of each fibre, 
the latter corresponding to the direction of the movement. 

Although these speculations concerning the function of giant fibres 
are purely tentative, they may serve as a basis for physiological 
experiments. 

c. Fibres of Set B. 

In describing the fibres of set B (Plate 4, Figs. 27, 28) I merely 
mentioned the fact of an anastomosis between the axis cylinders of the 
components of each pair. I wish here to discuss the subject more fully. 
The description of these fibres was by no means based wholly on meth- 
ylen-blue preparations. Indeed, all the facts, excepting that of anasto- 
mosis, were demonstrated on serial sections before an impregnation by 
methylen-blue was obtained. The fibres are so large that they can 
easily be traced through serial sections. This fact is important in con- 
sidering the value of the evidence for anastomosis. 

I have carefully examined seventeen pairs of these in serial sections 
cut in one or the other of the three cardinal planes of the body, and in 
addition eight pairs stained in methylen-blue and examined before cut- 
ting. Where the fibres of a pair crossed the ganglion they were always in 
contact with each other, and, with one exception, they ran parallel for a 
considerable distance. In the exceptional case the fibres crossed each 
other at an angle of about ten degrees, which still allowed a line of con- 
tact equal in length to one fourth the width of the ganglion. The fibres 
usually cross the ganglion at right angles to its longitudinal axis, but 
in one instance they crossed at an angle of about sixty degrees (Plate 1, 


7 


i 


i i  IN—AE OO ,, a 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 117 


Fig. 7). Thus, one of the fibres partially retraces its course in order to 
maintain a course parallel with its fellow. Sagittal sections (Plate 3, 
Figs. 22, 23) show that the fibres are always flattened on their apposed 
faces. That part of the sheaths which forms the dividing wall is usually 
very thin, and in some cases seems to be wholly wanting. In the prepa- 
rations: which are best preserved, however, the dividing wall can always 
be seen. I have not been able to demonstrate satisfactorily anastomoses 
in preparations made by the more usual histological methods. In 
methylen-blue preparations the fibres do not appear to be in contact, but 
this is due to a shrinking of the axis cylinder within the sheath produced 
during the fixing of the stain. The anastomoses, however, do exist, and 
are clearly shown in methylen-blue preparations (Plate 4, Fig. 28) ; they 
proceed from small elevations on the opposed faces of the fibres. From 
what has gone before, it is evident that the anastomosing bars simply 
pierce the thin membrane that separates the two fibres, and that they 
practically lie wholly within the fibre sheaths. Hence they cannot be 
regarded as fibrillations fused by the action of the methylen-blue. The 
fibrille of the axis cylinder pass out into the anastomosing bars, but 
whether they pass completely across from one fibre to the other I can- 
not say. There is, however, a distinct interdigitation of the fibrille of 
the opposite fibres. The appearance of the preparations gives one the 
impression that there has been a breaking of the fibrille of the anasto- 
moses due to the shrinking of the fibres. The anastomoses are not 
always as evident as they are in the case reproduced in Figure 28, but 
there is always some indication of them. This may consist simply of the 
pointed elevations arranged in pairs opposite each other on the fibres. 

Since the cells of set B are situated in a central organ, they are prob- 
ably motor, and since the fibres are united in bilaterally symmetrical 
pairs, they probably act in concert. Such animals as Annelids differ 
from more complex organisms in that many of their movements are in 
unison on the two sides of the body. The longitudinal contractions and 
expansions of the body are examples. In Nereis the movement of all the 
parapodia backward or forward, when the animal is touched at one end 
or the other, is another instance. When such movements are so fre- 
quent and of such vital importance, one may well expect to find an inti- 
mate association of the related nerve fibres. 

Allen (’96) describes decussating nerve elements in the abdominal 
ganglia of the lobster so closely united that he was unable to resolve 
them into their constituent parts. He finds, however, that similar ele- 
ments in the thorax are not so intimately related. .At another place he 


118 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


makes the statement that these elements of the abdomen innervate the 
abdominal muscles, while those of the thorax go to the ambulatory ap- 
pendages, The reason for the difference in the arrangement of the nerve 
elements will be immediately perceived. The muscles of the abdomen 
act bilaterally in unison, hence the union of the associated nerve elements. 
In the case of the ambulatory appendages there is little movement in 
unison, hence the corresponding independence of the fibres concerned. 


d. Fibres of Set C. 


Lenhossék (’92) makes the general statement relative to the sensory 
fibres of the earthworm, that they do not cross the ventral nerve cord, 
but end in fibrillations on the side from which they enter the cord. 
The fibre C of Nereis is an interesting exception to this rule. Concern- 
ing the anastomoses of this system I need say but little. The fibres are 
so large, the anastomoses so numerous and distinct, and the fibre in such 
excellent condition for study, that there is small chance for error, There 
is no vacuolation of the fibre nor other evidence to lead one to conclude 
that there has been a fusion of fibrillations in the manner suggested by 
Cajal (’96). I have seen no evidence of anastomosis between fibres 
except those of set Band set C, and here the anastomosis is always 
between fibres of the same set. 

I wish to call attention to one more point relative to these fibres. 
The small decussating branches cross the ganglion by a sinuous course, 
and yet where they cross each other they are invariably in contact. 
Why this should be so is difficult to say, unless the function of the fibres 
necessitates such contact. A similar relationship is also to be found be- 
tween fibres of other sets, as in the case of the fibres of sets A and B, as 
described above. Although physiologists do not recognize contact be- 
tween axis cylinders as a means of bringing fibres into functional re- 
lation, it seems to me quite probable that such a relation exists in 
some cases. 


SUMMARY. 


1. The central nervous system of Nereis virens occupies a deeper 
position than does that of most Polychetes. It is separated from the 
hypodermis by the circular muscles, and is enveloped by an elaborate 
protective tissue. 

2. The protective tissue consists of two parts ; an inner spongy layer, 
the neuroglia, of ectodermic origin, and an outer sheath, the neurilemma, 
of mesodermic origin, 


IAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 119 


3. The “mushroom bodies” of insects and decapod Crustacea are 
represented in the brain of Nereis by the anterior masses of small 
nuclei. 

4, The optic ganglion, which in some species of Nereis lies beneath 
the anterior eye, may in other species lie within the brain capsule. 

5. There is no neuropil in the ventral nerve cord. 

6. There are three longitudinal connectives between each two succes- 
sive ganglia of the ventral nerve cord, one small median and two larger 
lateral ones. 

7. The sheaths of the nerve fibres of the ventral cord have no nuclei, 
and hence must be a product of the fibres themselves. 

8. The nerve cells of the ventral cord commonly have one or more 
centrosomes. 

9. The giant fibres are nervous in function, and are put into relation 
with peripheral organs through ordinary centrifugal fibres. 

10. The giant fibres give off no fibrillations, and nervous relation with 
other fibres is established directly between the axis cylinders. 

11. Certain decussating fibres are always united in pairs by anasto- 
moses between the axis cylinders where they cross each other. 

12. Certain centripetal fibres of the same set are always united by 
anastomoses between the ends of the branches. 

13. Contact between axis cylinders may possibly be one of the means 
of bringing nerve fibres into functional relation with each other. 


In conclusion, I wish to acknowledge my indebtedness to Professor 
E. L. Mark for kindly advice and assistance rendered me in many ways 
while pursuing my studies in the Zéological Laboratory of Harvard Uni- 
versity. I gladly avail myself of this opportunity to express to him my 
sincere thanks. 


VOL. XXXII. — NO. 6. 3 


120 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


BIBLIOGRAPHY. 


Allen, E. J. 
°94. Studies on the Nervous System of Crustacea. Quart. Jour. Micr. Sci., 
Vol. 36, N. S., pp. 461-498, Pls. 35-38. 


Allen, E. J. 
°96. Studies on the Nervous System of Crustacea. Quart. Jour. Mier. Sci., 
Vol. 39, N. S., pp. 33-50, Pl. 4. 


Bethe, A. 
°95. Studien iiber das Centralnervensystem von Carcinus Maenas, nebst 
Angaben iiber ein neues Verfahren der Methylenblaufixation. Arch. f. 
mikr. Anat., Bd. 44, Helt 4, pp. 579-622, Taf. 34-36. 


Buehler, A. 
°95. Protoplasma-Structur in Vorderhirnzellen der Eidechse. Verhandl. phys.- 
med. Gesellsch. zu Wurzburg, N. F., Bd. 29, No. 6, pp. 209-252, 
Taf. 3-5. 
Also separate, 44 pp., 3 Taf., 1895. 


Cajal, Ramon y. 
°96. Nouvelles contributions 4 l’étude histologique de la rétine et a la ques- 
tion des anastomoses des prolongements protoplasmiques. Jour. Anat. et 
Physiol., Tome 32, No. 5, pp. 481-543, Pls. 12-15. 


Carriére, J. 
°85. Die Sehorgane der Thiere vergieichend-anatomisch dargestellt. Mimnchen 
und Leipzig. vi-+ 205 pp., 147 Abbildg. 


Cerfontaine, P. 
92. Contribution A l’étude du systéme nerveux central du Lombric terrestre. 
Bull. Acad. roy. Belgique, Série 3, Tome 23, pp. 742-752, Pls. 1, 2. 


Dahlgren, U. 
°97, A Centrosome Artifact in the Spinal Ganglion of the Frog. Anat. An- 
reiger, Bd. 13, No. 4, 5, pp. 149-151, 2 Figs. 
Ehlers, E. 
64-68. Die Borstenwiirmer (Annelida chetopoda) nach systematischen und 


anatomischen Untersuchungen dargestellt. Leipzig, Engelmann, xx + 748 
pp-, 24 Taf. 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 121 


Eisig, H. 
87. Monographie der Capitelliden des Golfes von Neapel und der an- 
grenzenden Meeres-Abschnitte nebst Untersuchungen zur vergleichenden 
Anatomie und Physiologie. Fauna u. Flora des Golfes von Neapel. 
Monographie XVI., Berlin, xxvi + 906 pp., 37 Taf. 
Friedlander, B. 

88. Beitrage zur Kenntnis des Centralnervensystems von Lumbricus. Zeit. 

f. wiss. Zool., Bd. 47, Heft 1, pp. 47-84, Taf. 9, 10. 
Friedlander, B. 

°89. Ueber die markhaltigen Nervenfasern und Neurochorde der Crustaceen 
und Anneliden. Mitth. Zool. Stat. Neapel, Bd. 9, Heft 2, pp. 205-265, 
Taf. 8. 

Friedlander, B. 

94. Altes und Neues zur Histologie des Bauchstranges des Regenwurms 

Zeit. f. wiss. Zool., Bd. 58, Heft 4, pp. 661-693, Taf. 40. 
Friedlander, B. 

°95. Ueber die Regeneration herausgeschnittener Theile des Centralnerven- 
systems von Regenwiirmern. Zeit. f. wiss. Zool., Bd. 60, Heft 2, pp. 249- 
283, Taf. 13, 14. 

Graber, V. 

°79. Morphologische Untersuchungen iiber die Augen der freilebenden mari- 
nen Borstenwiirmer. Arch. f. mikr. Anat., Bd. 17, pp. 243-323, Taf. 
18-20. 

Haller, B. 

*89. Beitrige zur Kenntniss der Textur des Central-Nervensystems hoherer 
Wiirmer. Arbeit. Zool. Inst. Wien, Tome 8, Heft 2, pp. 175-312, Taf. 
16-20. 

Hatschek, B. 

°89-91. Lehrbuch der Zoologie, u.s. w. Lieferungen 1-3. Jena, G. Fischer. 

432 pp. [unfinished]. 
Heidenhain, M. 

°97. Ueber die Mikrocentren mehrkerniger Riesenzellen, sowie tiber die Cen- 
tralkorperfrage im Allgemeinen. Morphol. Arbeiten [Schwalbe], Bd. 7, 
Heft 1, pp. 225-280. 

Jourdan, E. 

84. Le cerveau de |’Eunice Harassii et ces rapports avec l’hypoderme. 

Comptes Rendus Acad. Sci. Paris, Tome 98, pp. 1292-1294. 
Kenyon, F. C. 

*96. The Brain of the Bee. Jour. Comp. Neurology, Vol. 6, No. 3, pp. 

133-210, Pls. 14-22. 
Krieger, K. R. 

80. Ueber das Centralnervensystem des Flusskrebses. Zeit. f. wiss. Zool., 

Bd. 33, Heft 4, pp. 527-594, Taf. 31-33. 


122 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Lang, A. 
°88-~94. Lehrbuch der vergleichenden Anatomie der wirbellosen Thiere. 
Jena, G. Fischer, 1888-94, xvi + 1198 pp., 251 Abbildg. 


Lenhossék, M. von. 
792. Ursprung, Verlauf und Endigung der sensibeln Nervenfasern bei Lum- 
bricus. Arch. f. mikr. Anat., Bd. 39, Heft 1, pp. 102-136, Taf. 5. 


Lenhossék, M. von. 
°95. Centrosom und Sphare in den Spinalganglienzellen des Frosches. Sitzb. 
phys.-med. Gesellsch. Wiirzburg, Jahr. 1895, No. 5-7, pp. 79-103. 


Lenhossék, M. von. 
°95*. Centrosom und Sphare in den Spinalganglienzellen des Frosches. Arch- 
f. mikr. Anat., Bd. 46, Heft 2, pp. 345-369, Taf. 16, 17. 


Lewis, M. 
796. Centrosome and Sphere in Certain of the Nerve Cells of an Invertebrate. 
Anat. Anzeiger, Bd. 12, No. 12, 13, pp. 291-299, 11 Figs. Sept. 2. 


McClure, C. F. W. 
796. On the Presence of Centrosomes and Attraction Spheres in the Ganglion 
Cells of Helix Pomatia, with Remarks upon the Structure of the Cell Body. 
Princeton Coll. Bull., Vol. 8, No. 2, pp. 38-41. 


Quatrefages, A. de. 
°50. Etudes sur les types inférieures de l’embranchement des Annelés. Ann. 
Sci. Nat., Série 3, Zool., Tome 14, pp. 281-289. 


Racowitza, E. G. 
°95. Sur le réle des. Amibocytes chez les Annélides polychétes. Comptes 
Rendus Acad. Sci. Paris, Tome 120, No. 8, pp. 464-467. 


Racowitza, E. G. 
96. Le lobe céphalique et l’encéphale des annélides polychétes. (Anatomie, 
morphologie, histologie.) Arch. Zool. Exp., Série 3, Tome 4, No. 1, 2, 
pp. 133-343, Pls. 1-5. 
Rath, O. vom. 
95. Zur Conservirungstechnik. Anat. Anzeiger, Bd. 11, No. 9, pp- 280- 
288. 


Retzius, G. 
91, Zur Kenntniss des centralen Nervensystems der Wiirmer. Biol. Unters., 
N. F., Bd. 2, pp. 1-28, Taf. 1-10. 


Retzius, G. 
°95. Zur Kenntniss des Gehirnganglions und des sensiblen Nervensystems 
der Polychiten. Biol. Unters., N. F., Bd. 7, pp. 6-11, Taf. 2, 3. 


Rohde, E. 
’87. Histologische Untersuchungen iiber das Nervensystem der Polychiaten. 
Zool. Beitrage [Schneider], Bd. 2, Heft 1, pp. 1-81, Taf. 1-7. 


HAMAKER: NERVOUS SYSTEM OF NEREIS VIRENS. 123 


Sars, M. 

35. Beskrivelser og iagttagelser over nogle meerklige eller nye i Havet ved 
den Bergenske Kyst lebende Dyr, af Polypernes, Acalephernes, Radia- 
ternes, Annelidernes og Molluskernes Classer, etc. Bergen. 81 pp., 
15 pls. 

Schaffer, J. 

°96. Ueber einen neuen Befund von Centrosomen in Ganglien- und Knorpel- 
zellen. Sitzb. Akad. Wissensch. Wien, math.-naturw. Cl., Bd. 105, Heft 
2, Abth. 3, pp. 21-28, 1 Taf. 


Schréder, G. 
86. Anatomisch-histologische Untersuchung von Nereis diversicolor, O. Fr. 
Mill. Inaug.-Dissertation. Rathenow. Carl Koppel. 43 pp., 1 Taf. 
Spengel, J. W. 
*81. Oligognathus Bonelliz, eine schmarotzende Eunice. Mitth. Zool. Stat. 
Neapel, Bd. 3, Heft 1 u. 2, pp. 15-52, Taf. 2-4. 


Vejdovsky, F. 
°88-'92. Entwicklungsgeschichtliche Untersuchungen. Prag, iv + 401 pp., 
u. Atlas mit 32 Taf. 
Vignal, W. 
°83. Recherches histologiques sur les centres nerveux de quelques invertébrés. 
Arch. Zool. Exp., Série 2, Tome 1, No. 2, pp. 267-412, Pls. 15-18. 
Vom Rath, O. See Rath, O. vom. 
Waldeyer, W. 
°91. Ueber einige neuere Forschungen im Gebiete der Anatomie des Central- 


nervensystems. Deutsch. med. Wochenschrift, Jahrg. 1891, No. 44. 
Also separate. G. Thieme, Leipzig, 1891, 64 pp., 10 Figs. 


Wawrzik, E. 
°92. Ueber das Stiitzgewebe des Nervensystems der Chaetopoden. Zool. Bei- 
triage [Schneider], Bd. 3, Heft 2, pp. 107-127, Taf. 14-19. 


124 


BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


EXPLANATION OF PLATES. 


All Figures, except 1, 5, 8, 27, and 39, were outlined with the camera lucida. 
Figures 28-30 and 32-41 were drawn from methylen-blue preparations. 


a. 
anastm. 
ax. cyl. 
ceb. 
cir. 

cir. ta. 
el. cil. 
cl. sns. 


coms. Crc-@. 


con’t. lg. 1. 


con’t. Ig. m. 


c’so. 

cta. 
di’sep. 
Sor. 
Sor. mot. 
Sor. n. 


gn. coms. 
gn. pa’pd. 
gn. sb-e. 


ABBREVIATIONS. 

Anterior. gn. sq. 
Anastomosis. h’drm. 
Axis cylinder. mu. 
Brain. mu. ere 
Cirrus. mu. lg 
Tentacular cirrus. mu. ob 
Ciliated cell. n. 
Sensory cell. n’cd 
Circum-cesophageal com- n’gli. 

missure. nl. 
Lateral longitudinal con- nlem 

nective. n’pil 
Median longitudinal con- n, pa-coms. 

nective. oc. 
Centrosome. p: 
Cuticula. po. sg. 
Dissepiment. rtl. 
Fibrillations. Sg. Ce. 
Motor fibres. set. 
Nerve fibres. sul. cil. 
Commissural ganglion. tu. for. 
Parapodial ganglion. tu. t. 


Sub-cesophageal ganglion, 


va. sng. 


Segmental ganglion. 
Hypodermis. 

Muscle fibres. 
Circular muscles. 
Longitudinal muscles. 
Oblique muscles. 
Nerve. 

Giant fibre. 
Neuroglia. 

Nucleus. 
Neurilemma. 
Neuropil. 
Para-commissural nerve. 
Eye. 

Posterior. 

Pore of segmental organ. 
Reticulum. 

Cephalic segment. 
Seta. 

Ciliated groove. 
Fibre sheath. 

Tunica intima. 
Blood-vessel. 


Hamaker. — Nervous Syst. Nereis. 


Fig. 1. 


Fig. 2. 


Fig. 3. 
Fig. 4. 


Fig. 5. 


Fig. 6. 


Fig. 7. 


Fig. 8. 


PLATE 1. 


Diagram showing the disposition of the nerves of the brain and sub- 
cesophageal ganglion in dorsal aspect. In order to show the commissural 
ganglion and its nerves, the right anterior eye has not been indicated; 
I, V, a, 8, y, nerves to the proboscis; II, nerve to the antenna; III, IV, 
VII, 5, «, G 7, nerves to the muscles and the general surface of the head; 
6, commissure between the anterior and posterior cirrus ganglia; VI, 
nerve to the palp; VIII, IX, X, nerves from the brain to the commis- 
sural ganglion; XI, XII, optic nerves; XIII, nerve of the ciliated 
groove; XIV, three openings in the dorsal surface of the brain capsule, 
through which loose bundles of nerve fibres pass to the integument of 
the mid-dorsal region of the cephalic lobe. 

Para-sagittal section of a giant fibre to show the passage through it of a 
fibre of set B (compare Fig. 27). In this case the branching of the fibre 
B takes place within the giant fibre, and the axis cylinder of fibre B is 
shrunken. 

Cross section of a lateral giant fibre, to show the reticulum. 

Frontal section of the body wall between two parapodia, to show the rela- 
tive positions of nerves IV’, V’, and I’, and of the attachment of the 
longitudinal muscles and the dissepiment. 

Diagram of posterior aspect of part of a cross section, showing the dispo- 
sition of the parapodial nerves. The second and third parapodial nerves 
(compare Fig. 8) are designated by 2 and 3 respectively. 

Frontal section of a segmental ganglion, showing the intimate relation 
between the fibres of sets A and B (compare Fig. 27). 

Section similar to that in Fig. 6 showing the relation of the decussating 
parts of fibres 6B; also showing exceptional oblique course across the 
ganglion. 

Diagram showing the disposition of the segmental and parapodial nerves 
of a typical segment. JI, II, III, 1V, V, the five segmental nerves num- 
bered from in front backward. 1, 2, 3, 4, the four parapodial nerves. 


PEATE 1. 


HamAKER. — Nervous Syst. Nereis. 


PLATE 2. 


Fig. 9. Transverse section through the posterior end of the brain. 

Fig. 10. Pigment (?) from the posterior part of the brain. 

Figs. 11 and 12. Nerve cells of the fourth and third classes of the brain respectively. 

Fig. 13. A group of four ganglionic cells of a ene ganglion, in frontal 
section, to show centrosomes. 

Fig. 14. A, ordinary ganglionic cell. &, one of the large cells of set B (compare 
Fig. 27). The cytoplasm is not granular and takes little stain, ex- 
cepting the large irregular granules around the centrosomes. 

Fig. 15. Brain nerve cell of the second class. 

Figs. 16 and 17. Brain nerve cells of the sixth class. 

Fig. 18. Transverse section through the posterior end of a segmental ganglion 
from the region of the fifteenth segment. It shows the connection 
between the neurilemma and the tunica intima of the ventral blood- 
vessel; also the position of the ventral nerve cord relative to the hypo- 
dermis and the circular muscles. 

Fig. 19. Brain nerve cell of the fifth class. 


Nitro 


JUHA. 


HamAkKeER. — Nervous Syst. Nereis, 


PLATE 3. 


Fig. 20. Parasagittal section of the cephalic segment tangent to the lateral surface 
of the posterior eye, to show the ciliated groove. 

Fig. 21. Enlarged view of part of Figure 24, to show the arrangement of the 
nuclei of the “mushroom body.” 

Figs. 22 and 23. Para-sagittal sections of fibre A (compare Fig. 27), showing 
relation to fibres B, and also contact of fibres B with each other. 
The median giant fibre also appears in Fig. 23. 

Fig. 24. Transverse section through the anterior part of the brain, showing the 
“mushroom body.” 

Fig. 25 is omitted. 

Fig. 26. Frontal section of a longitudinal connective. 


~Wdrm 


, 


| 


iy (Orv. A ( 


MAK R-Nexvous Sysr Nereis. 


HAMAKER. — Nervous Syst. Nereis. 


Fig. 27. 


Fig. 28. 
Fig. 29. 


Fig. 30. 


PLATE 4. 


Diagram to illustrate the fibre systems of sets A, B, and C, in two succes- 
sive ganglia, as projected on the frontal plane. 

A pair of anastomosing fibres of set B. 

Fibres of set C, showing anastomosis between a posterior and a decus- 
sating branch. 

Fibres of set C, showing anastomosis between an anterior and a posterior 
branch. 


= 
gE 4. 


PLaT 


c 
we 


Nervous Syst. Nervi: 


HAMAKER- 


Fig. 
Fig. 


HAMAKER. — Nervous Syst. Nereis. 


32. 


PLATE 5. 


Transverse section of the longitudinal connectives of the ventral cord. 

Frontal section of the ventral ramus of a parapodium (compare Fig. 8), 
showing motor (?) elements in the posterior branch of the second 
parapodial nerve. 

A section similar to that in Figure 32, showing sensory elements in the 
second parapodial nerve. 

Motor fibres and endings in the longitudinal muscles. 

Sensory cell from the base of a parapodium. 

Sensory cell from the side of the body near the fourth segmental nerve. 

Sensory nerve termination from the anterior wall of the parapodium. 

Sensory cell from the posterior wall of the parapodium. 

Diagram to show the course of fibres in the parapodial ganglion. 

Fibres of the ‘“‘sub-hypodermal plexus” ending among the glands of the 
hypodermis. 

A nerve fibre showing the spiral arrangement of the fibrille, and also the 
shrinking of the axis cylinder from its sheath. 


PLatTe 5, 


ftér wot 


mee cre. 


Bulletin of the Museum of Comparative Zoology 
AT HARVARD COLLEGE. 
VOL. Zee XT, No. T. 


ON REMAINS OF STRUTHIOLITHUS CHERSONENSIS 
FROM NORTHERN CHINA, 


WITH REMARKS ON THE DISTRIBUTION OF 
STRUTHIOUS BIRDS. 


By C. R. Eastman. 


Wirn One Puarn. 


CAMBRIDGE, MASS., U.S. A.: 
PRINTED FOR THE MUSEUM. 


Aveusrt, 1898. 


eS ek 


No. 7. — On Remains of Struthiolithus chersonensis from North- 
ern China, with Remarks on the Distribution of Struthious 
Birds. By C. R. EAstMan. 


In the year 1857, or thereabouts, a remarkable fossil egg was discov- 
ered in the Government of Cherson, in South Russia. The circumstances 
of its being brought to light were peculiar, and its subsequent history 
is instructive enough to repay a brief recapitulation, which we give as 
follows. 

During a spring freshet, a small stream occupying an old watercourse 
excavated a hollow below a milldam near the village of Malinowka, in the 
Chersonesus. Some peasants happening by at the time observed floating 
on the surface of the pool an egg-shaped object, which they lost no time 
in capturing. A neighboring freeholder acquired the specimen, and from 
him it passed into the possession of his nephew, a man by the name of 
Dobrowolsky, who offered it for sale to various Russian institutions. 
Declined by all on account of the exorbitantly high price demanded for 
it (1,000 roubles), it was preserved in the family for over twenty-five 
years, until through a deplorable mishap it was shattered into nearly 
forty pieces. Some of the fragments, however, were obtained by Pro- 
fessor W. von Nathusius, who examined them microscopically, and 
declared that they indicated a very close relationship to the common 
ostrich.? 

But long before the destruction of this unique specimen, namely, in 
the year 1872, Professor A. Brandt of Charkow, to whom it was sub- 
mitted by the owner, had the forethought to take a plaster cast of the 
fossil, and at the same time prepared a minute description of it. We 
are indebted to him for our principal knowledge of this egg, as well as 
for the news of the fatality that ultimately overtook it.? 


1 Zoolog. Anzeiger, Vol. IX. No. 214, p. 47 (1886). 

2 Bull. de l’Acad. Imp. des Sci. St. Petersburg, Vol. XVIII. pp. 158-161 (1873) ; 
Mélanges Biol., Vol. VIII. pp. 730-735; Ibis, [3], Vol. IV. pp. 4-7 (1874); Zoolog. 
Anzeiger, Vol. VIII. No. 191, p. 191 (1885). 

VOL. XXXII. — NO. 7. 1 


128 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


The matrix from which the specimen was washed out is stated by 
Brandt to have been a reddish brown friable loam, overlying a bed of 
crystalline gypsum. So symmetrical was the shell in outline that it 
was wellnigh impossible to determine which end corresponded to the 
acute, and which to the obtuse pole of ordinary birds’ eggs.’ Being 
perfectly intact, little more could be done than to note its general ex- 
ternal appearance, and ascertain its weight and dimensions. The weight, 
which fell a trifle short of two Russian pounds, was found to be dispro- 
portionate to the thickness, but is probably to be accounted for by the 
mineral infiltration observed by Nathusius. According to the latter, 
portions of the interior were lined with a crystalline deposit having a 
thickness of 1.8 cm. in places, and there was also a quantity of loose cal- 
careous matter within the ovulite, supposed to represent the fossilized 
membrana teste. 

The capacity of the egg, that is to say, its cubic contents, was deter- 
mined by Brandt indirectly from the displacement of a plaster cast 
in water, which amounted to upwards of 2200 c.cm. Allowing say 
125 c.cm. for the volume of the shell substance itself, the actual capacity 
of the interior is seen to be about 2075 c.cm., as indicated in the table 
on page 133. Now, as the shell of the largest known ostrich egg has 
only two thirds this capacity, it is plain that the fossil egg must be the 
legacy of a larger bird than the ostrich, and very likely one differing in 
other respects as well as size. That the egg belonged to some Struthions 
bird is shown in a convincing manner by the microscopic structure, 
which is eminently characteristic of the group.” But in the absence of 
direct skeletal evidence, such as might have been afforded by associated 
bones, it seems inadmissible to refer so huge an egg to the same genus 
as the living ostrich. Therefore we are inclined to dissent from the 
proposition of Nathusius to abandon the genus Struthiolithus, which 
was very properly created for its reception by Brandt, and agree with 


1 On the cause and significance of polar deformation of egg shells, compare the 
following suggestive papers: Ryder, J. A., The Mechanical Genesis of the Form of 
the Fowl’s Egg (Proc. Amer. Philos. Soc., Vol. XX. XI. (1893), pp. 203-209) ; Wick- 
mann, H., Die Lage des Vogeleies im Eileiter vor und wihrend der Geburt (Journ. 
fiir Ornithologie, Vol. XLIV. (1896), pp. 81-92). 

2 Nathusius, W. v., Ueber die Eischalen von Aepyornis, Dinornis, Apteryx, ete. 
(Zeitschrift fiir wissensch. Zool., Vol. XXI. (1871), pp. 880-856) ; Ueber die char- 
acteristischen Unterscheidungszeichen verschiedener Straussen-eier (Journ. fiir 
Ornithol., Vol. XXIII. (1885), pp. 165-178) ; Hutton, F. W., On the Microscopical 
Structure of the Egg Shell of the Moa (Trans. New Zealand Inst., Vol. 1V. pp. 
166, 167), 1872. 


~~ OO __ 


EASTMAN: REMAINS OF STRUTHIOLITHUS CHERSONENSIS. 129 


the latter in retaining it, provisionally at least, or until information 
is at hand concerning the creature itself. The specific title applied 
by Brandt to the ovulite and its as yet unknown parent bird is 
S. chersonensis. 

According to Eichwald, fossil avian remains are extremely scarce in 
Russia. An instance is reported by von Nordmann, however, where 
certain bones were recovered from Tertiary deposits near Odessa, but no 
hint is given as to their probable affinities. The Pliocene of the Siwalik 
Hills in India, as is well known, has yielded ostrich remains which 
indicate a species (S. asiaticus) apparently closely related to S. camelus ; 
and other fragments, described as S. karatheodoris, have been found in 
the Lower Pliocene of Samos. 

Up to the present time no further examples, either of egg shells or 
of the skeleton of S. chersonensis have come to light; and as already 
remarked, all that remains of the unique type are the fragments said to 
be still preserved in the St. Petersburg Museum. We have, therefore, 
no little satisfaction in being able to announce the discovery of a second 
perfect specimen, which has recently found its way to this country from 
China. The configuration of the shell and much of its surface detail 
are shown on the accompanying plate, which has been reproduced from 
photographs. The history of the new specimen is as follows. Four or 
five years ago, a Chinese farmer, while working at the foot of a bank of 
earth about six meters high, dug out what he considered to be a pair of 
“dragon’s eggs.” One was broken, the other entire, and, presuming 
the latter to have some commercial value, he took it with him to Kal- 
gan, and disposed of it to Rev. William P. Sprague, one of the American 
Board missionaries residing there. Rev. James H. Roberts, a brother 
missionary who has also spent many years in China, was present when 
the egg was sold, and on revisiting this country last spring brought the 
specimen with him on behalf of Mr. Sprague, to be offered for sale 
to some scientific institution. Eventually it was purchased for the 
Museum of Comparative Zodlogy, where it is now deposited. 

The Chinese workman who found the egg was well known to the 
servants of the missionaries as a man living in Yao Kuan Chuang. This 
is a small village in the district of Hsi Ning, about fifty miles south- 
southwest from Kalgan by road, but somewhat nearer in a straight line, as 
that region is very mountainous. Subsequently Mr. Sprague visited the 


1 The circumstance of two eggs being found together accords well with Owen’s 
Suggestion that the oviposition of the moa was probably in pairs. Cf. Extinct 
Wingless Birds of New: Zealand, Vol. I. p. 320, 1879. 


130 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


exact spot where the eggs were dug up, in company with the man who 
found them, and thns satisfied himself of the authenticity of the dis- 
covery. The fragments of the second specimen were unfortunately not 
preserved, and as Mr. Sprague was in donbt whether the perfect one 
was indeed an egg or perhaps only a geode, he cut a hole about 1.5 em. 
in diameter at one end, to ascertain if there were crystals on the inside. 
But on reflecting light into the interior, the walls were seen to present 
the same general appearance as the external surface, and a loose calca- 
reous mass, partly in the form of powder and partly flakes that appear 
to have become scaled off from the inner surface, was found within the 
cavity. This mass is still preserved in the same condition as when 
found, and weighs 18.1 grams. Possibly it represents in part the 
calcified shell membranes, such as have been found fossilized in certain 
moa eggs. Examined with a pocket lens, the flakes present no appear- 
ance of having an organized structure. 

Before proceeding to a description of the egg, it may be of interest 
to note some of the topographical features of the region as depicted by 
Mr. Roberts in the following sketch, which he was kind enough to draw 
up at the writer’s request : — 


“The city of Kalgan numbers about 100,000 inhabitants, and lies 140 miles 
northwest of Peking, China. Having lived there ever since 1880, I am famil- 
iar with the city, and all the surrounding section of country. The village of 
Yao Kuan Chuang I have frequently visited on my preaching tours to Yii 
Chou and Hsi Ning. The Hsi Ning (Western Repose) valley extends from 
W.S. W. to E. N. E., being from seven to ten miles wide near its eastern end, 
but at a distance of more than thirty miles from that end it begins to widen 
gradually toward the west. Yao Kuan Chuang is situated about twenty miles 
from the eastern end, and two miles from the mountains on the north, 
Through the valley, from west to east, flows the Sang Kan (Mulberry Dry), 
which is the largest river in the region northwest of Peking. It has no bridges, 
except in winter, but is fordable in certain places. The Hu Liu (Pot Flow) 
River, flowing northeast past Yii Chou and then north, joins the Sang Kan at a 
point three miles east of Yao Kuan Chuang. The Hsi Ning valley, except at 
its western end and where the Hu Liu River comes in, is walled with moun- 
tains several hundreds of feet above the river. The elevation above sea level, 
at the junction of the Sang Kan and Hu Liu, is shown by the barometer to be 
about 2740 feet. The mountains present the appearance of bare rock, gullied 
out in former times by glacial ice, and so steep that grass cannot grow on the 
larger part of their surface. The rocks are stratified, tilted up at a high angle, 
and contain a large amount of mica. In one place sheets of mica are taken out 
for commercial purposes, to be made into window panes. 

“There are extensive formations of loess in the Yti Chou and Hsi Ning 


xX ye) oso 


EASTMAN: REMAINS OF STRUTHIOLITHUS CHERSONENSIS. 131 


valleys, from fifty to a hundred feet deep; but the loess, or yellow clay, has 
been worn away from the greater part of the land north of the Sang Kan River, 
so that sand and gravel predominate. Wherever irrigated by a stream from 
the mountains, the land becomes very good and fertile. Near the eastern end 
of the Hsi Ning valley the Sang Kan River enters a narrow gorge, through 
which it flows ten or thirteen miles to the lower valley of the Pao An. Hach 
of these valleys was once a lake, walled in by the mountains around them. 
The evidence of this is unmistakable. As to the Hsi Ning valley, the Chinese 
say it is recorded in their histories that it was occupied by a lake until about 
the year 1000 a.p., when the waters cut through the mountains, and the lake 
was drained off. The recent date assigned to this event, and the general accu- 
racy of Chinese history, would seem to make the story credible, while the 
configuration of the land shows that such an occurrence must have taken place. 
Now the valley is tilled very carefully, and villages of a hundred families are 
interspersed only two or three miles apart. The soil is mostly poor and grav- 
elly, but the stones in it, heated by the sun, radiate their heat at night, and 
the mountain range on the north is frequently visited with rain; yet the 
climate on the whole is rather arid. 

“ Just north of Yao Kuan Chuang is a remarkable seam of red rock [erup- 
tive dike?] eighty feet thick, intersecting the mountains in a vertical plane. 
It is very conspicuous in contrast to the brown-colored mountain, and is alleged 
by the natives to be the trail of a serpent. Eight miles west of Yao Kuan 
Chuang is a ridge composed of small rounded pebbles and rock fragments 
[esker ?], which extends from the foot of the northern mountains to the river, 
a distance of about two miles. Farther west are a large number of craters, the 
widest being about two miles in diameter, and containing numerous smaller ones. 
Seventeen miles southwest of Yao Kuan Chuang, on the opposite side of the 
river, is Fu T’ou Chiang, a market for coal, which is brought in large blocks 
on mules from the southern mountains. This coal is of two kinds, one that 
smokes, and one that does not; and the chief peculiarity of both kinds is that, 
if any part of a block gets on fire, the whole will slowly consume away, leaving 
only white ashes. A lump of it as big as a man’s fist, if covered with ashes, 
will keep a fire all night.” 


Reference to the works of von Richthofeu! and Pumpelly? on the geol- 
ogy of China shows that the above account is in substantial agreement 
with the descriptions of the surrounding region, as furnished by these 
authors. Both of them comment on the desiccation that has taken place 
within comparatively recent times, and note the traces of former shore 
lines along the mountain sides. The lower part of the Sang Kan flows 
through a synclinal valley, and higher up in its course it drains a number 
of loess basins, from one of which our fossil was derived. According to 


1 Richthofen, F. Fr. von, China, Vols. I.-III. Berlin, 1883. 
2 Pumpelly, R., Across America and Asia. 2d edition, New York, 1872. 


132 - BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


von Richthofen,' the superficial deposits of these basins were laid down 
over the bottoms of isolated salt lakes having no outlet, and were after- 
wards partially buried by alluvial detritus. The moderate depth to 
which ravines have cut through the ancient lake beds, and the straight 
narrow gorge of the Sang Kan, through which the waters were drained off, 
corroborate the belief that this event took place at no very remote period. 
At all hazards, it is certain that no earlier age can be assigned to the 
gravel beds from which the fossil egg was exhumed than the Pleistocene. 
Turning our attention now to the specimen itself, we notice that it 
presents almost exactly the same appearance as the Russian egg de- 


scribed by Brandt, a comparison with which has been facilitated by | 


means of a plaster cast very kindly presented to the Museum by this 
author. In size, symmetry of contour, and all outward respects, the 
two are remarkably alike. ‘The only noticeable difference is im respect 
to weight, but this is readily explained by the mineral infiltration already 
referred to in the case of the type, and the absence of such replacement 
in the present example. Assuming that none of the internal calcareous 
mass has been lost, the Chinese egg must have weighed originally about 
337 grams, as against “nicht ganz zwei russische Pfunde” for Brandt’s 
specimen. The weight of our individual, as given in the subjoined table, 
is for the empty shell, perforated at one end in the manner already de- 
scribed. The mutilation cannot be said to be altogether regrettable, 
however, since it permits of an inspection of the interior, and facilitates 
a measurement of the volume (equal to the loss of weight in water), 
cubic contents, and specific gravity of the object. 

Measurements of a number of other eggs were made in like manner, 
and the results are tabulated herewith for the sake of comparison. In 
the case of the South American ostrich, an average-sized and also a 
large-sized individual were selected from a collection of over two dozen 
contained in the Museum of Comparative Zodlogy. The dimensions of 
Epyornis and Dinornis eggs are taken from the literature of these 
genera, excepting No. 3 of the list, which were derived from a plaster 
cast obtained from the Paris Museum of Natural History. For these 
two genera the cubic contents have been calculated from the formula of 
an ellipsoid of revolution (since no data are at hand to show that they 
have ever been ascertained by direct experiment) and, not being cor- 
rected for the thickness of the shell nor for its departure from the figure 


1 Loc. cit., p. 344 et seg. Also Vol. I. p. 110, quoted in Whitney’s ‘ Climatic 
Changes” as follows: “It may be stated as a certainly ascertained fact, that 
in Central Asia a dry climate has prevailed for a long time.” 


ey 


TF 5ere~s 


133 


REMAINS OF STRUTHIOLITHUS CHERSONENSIS. 


. 
. 


EASTMAN 


TABLE SHOWING COMPARATIVE DIMENSIONS OF THE EGG SHELLS OF STRUTHIOUS BIRDS. 


Name of Species. 


Epyornis maximus Geoff. 


a oe se 
“ee eé sc 


“ “ ce 


DDEROMEIRD: 64 i$ sas — GIP hs 


Struthiolithus chersonensis Bat. 


“ce ce “ce 


Struthio camelus Linn. 


“ee “ “ee 


Rhea darwinit Gould . 


“ce “e “s 
: 


Rhea americana (Linn.) 


ay sé “ce 


Casuarius bennettt Gould 
f- australis Wall. . . 
Dromeus nove hollandice (Lath. ) 


Gallus gallus Linn.. . . . 


“pil 
2 
3 
4 
5 
6 
7 
8 
9 


a a | 
oT FR © DH SO 


[eurpngisuo0'y 


cm. 


24.5 
22.5 
23.0 
23.4 
Lifes 
15.0 
14.75 
13.40 
13.50 
9.45 
9.00 
9.95 
9.13 
9.00 
8.65 
8.08 
4.30 


“aoUaIOJUINIILY 
soley 
[emojenby 


“aOUIIATUIMIIID 


em. 


92.1 
85.0 
84.0 
84.8 
52.0 
51.35 
47.10 
46.00 
35.85 | 
34.60 
37.35 
35.90 
36.45 
32.80 
30.04 | 
15.55 | 13.40 


‘sexy JO oOnvY 


‘TRUS 


JO ssauyonyy, 


le 


819.+ 
310.05 
310.95 
79.89 
17.33 
106.64 
74.48 
73.86 
65.41 
63.47 
5.75 


125.4 
121.30 
125.82 
33.87 
35.79 
47.80 
31.58 
82.51 
28.46 
26.40 
2.62 


Cubic 
Contents. 


c.cm. 


11,035.8 
9,012.5 
8,863.5 
8,887.8 
4,180.6 


Remarks. 


Original in Brit. Museum, No. 41,847. 


vs “ Paris Museum. 


re ‘* Paris Museum. 
Plaster cast in M. C. Z. 


Figured by Owen and Rowley. 


2,075.1] Type specimen. 

1,896.90 | Chinese example. 

1,423.63 | Largest ostrich egg in M. C. Z. 

1,350.00} Brandt’s largest ostrich egg. 
570.44} From Sandy Point, Patagonia. 
500.75 From‘ Hf fe 


639.23 
534.84 
548.72 


“Brazil. 


“ “ 


‘¢ New Britain. 


439.43 | From Australia. 
847.67 | From Victoria, Australia. 


50.00 


| 


Medium-sized hen’s egg. 


154 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


of a perfect ellipsoid, are somewhat in excess of the true values. The 
capacity of all the other eggs was found by weighing them when filled 
with water, and reducing the results; hence the table can be relied 
upon as being more accurate than that based upon the computations of 
Geoffrey St.-Hilaire.’ 

This author asserts that the egg of pyornis is equal in capacity to 
6 ostrich eggs, or 12 of the nandu, 16.5 of the cassowary, 17 of the emeu, 
or 148 of the common fowl, assuming the latter to hold on the average 
60 c.cm. One arbitrary standard is as good as another, and, as the hen’s 
egg for which measurements are given (No. 19 of the table) happened 
to contain exactly 50 ¢c.cm., we may adopt it as our unit; whence it 
appears that a medium-sized emeu’s egg is equal to 7 such units ; a casso- 

wary’s (C. bennetti) 11; a nandu’s 10 to 12; an ostrich’s 27 ; a moa’s 84; 
and the largest known ‘Aigyoress egg no less than 220. It may be wae 
mentioning in this connection, for the benefit of those interested, that 
the eggs of Zpyornis and Dinornis have been sold at prices ranging 
between £100 and £200, and the price asked for the type of Struthio- 
lithus equals about $770 of our money. These fabulous prices are de- 
pendent, of course, upon the scarcity of the objects; for although egg 
fragments of the two first named genera are tolerably abundant, the 
number of perfect specimens all told is Jess than a score. 

But to return to the description of Struthiolithus. It is probable that 
the egg shell was only partially embedded in the soil when found, the 
evidence for this being that the greater portion of the surface is in- 
crusted, more or less granulated, and otherwise affected by atmospheric 
erosion. The least weathered side is that shown in Figure 2, on which 
several areas are to be observed where the original shell has remained 
unaltered. Some discoloration has been brought about through the 
agency of iron oxide, and grains of ferruginous sand still adhere to the 
shell in places, or are even partially embedded in the crust. This side 
of the shell is of a brownish yellow color, somewhat darker than the 
opposite or more weathered side, shown in Figure 1. Numerous fine 
pittings are to be seen over the greater part of the periphery, some of 
which may be due to destructive agencies, but the majority of them are 
clearly to be regarded as the round terminal pores of air canals. To 


1 Comptes Rendus, Vol. XXXII. (1851), p. 102. Cf. also Comptes Rendus, 
Vols. XX XIX. (1858), p. 833, and LXV. (1864), p. 476; Proc. Zoolog. Soc. London, 
1852, p. 9, and 1867, pp. 892-991; Ibis, [2], Vol. IV. (1868), p. 65; Ornithological 
Miscellany (G. D. Rowley), Vol. III. p. 237 (1878) ; Owen’s Extinct Wingless 
Birds of New Zealand, Vol. I. pp. 817-820 (1879). 


j 
: 
. 


— ae 


EASTMAN: REMAINS OF STRUTHIOLITHUS CHERSONENSIS. 135 


determine their precise relations it would be necessary to sacrifice a 
portion of one of the best preserved areas for the purpose of making 
a thin section ; but as no such area is contiguous to the aperture cut 
at the upper end by Mr. Sprague, no further incisions have been at- 
tempted. It is doubtful in any case whether a section would show more 
than has already been ascertained from Nathusius’s study of the type 
specimen, which merely proved that the air canals terminated in a 
similar fashion as in Struthio camelus. But the variations in the struc- 
ture of egg shells among different birds, or even in different parts of the 
same egg, are so considerable,’ that we are averse to depending upon 
this method for accurate systematic identification. In the opinion of 
the writer, the utmost we are warranted in affirming with regard to the 
relationship of Struthiolithus is, that it probably was very like the living 
ostrich, but not necessarily a member of the same genus; hence the 
propriety of retaining Brandt’s name in a tentative sense is apparent. 


The occurrence of fossil ostrich remains in the loess of such widely 
separated regions as Northern China and Russia has a direct bearing 
upon the distribution of Struthious birds. It enables us to speak 
positively with regard to the former extension of the Struthionid@ over 
Kur-Asia and Africa since the Pliocene, and gives rise to some infer- 
ences, within duly circumscribed bounds, regarding the past history of 
Raft-breasted birds in general. It is necessary to distinguish between 
what can be affirmed of the ostrich group, properly speaking, and what 
we can assume with more or less plausibility concerning the rest of the 
so-called Fatite. For, if it were possible to recognize the latter as a 
natural division, embracing forms genetically related to one another, or 
all derived from a common ancestral type (that is to say, a “ Ratite” 
type), then we should be warranted in establishing a single hypothesis of 
distribution for all branches of the Ratite. But the best modern orni- 
thological opinion holds that the division into Ratite and Carinate is 
unnatural, since the differences between existing species of Raft-breasted 
birds are nearly as great as between any of the Ratite and Carinate.2 


1 Blasius, R., Ueber die Bildung, Structur, und systematische Bedeutung der 
Kischale der Vogel. Leipzic, 1867, pp. 48. 

2 Cf. Fiirbringer, M., Untersuchungen zur Morphologie und Systematik der 
Vogel, Vol. II. p. 682. Amsterdam, 1888. Also (on the relations of Gastornis) 
under same caption in Biol. Centralblatt, Vol. XTX. pp. 578-587 (1898). On the 
taxonomic relations of Rhea, loc. cit. (1888), p. 1442; of Hesperornis, Ornith. Mo- 
natsber. deutsch. Vereins z. Schutze der Vogelwelt, Vol. XV. p. 488 (1890). 


136 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


For our present purpose, this question as to the homogeneous or 
compound character of the Ratite is of prime importance, involving as 
it does the problem of common or multiple origin for its several mem- 
bers, and hence the key note of their distribution. If we admit, for 
instance, as has been suggested by some, that the South American 
ostrich was derived from the tinamous or some other Carinate stock, 
then it must be altogether excluded from the list of forms that migrated 
into the western hemisphere by means of a former land connection. 
But if, on the other hand, structural resemblances are sufficient to point 
to a genetic relationship with the ostrich or other Struthious type, 
then its occurrence in Patagonia can be accounted for in no other way 
than on the hypothesis of a land migration. 

Or again, in the case of the remarkable Stereornithes, from the early 
Tertiary of Argentina and Patagonia, which were considered by Ame- 
ghino, Gadow, and for a time also by Lyddeker, as ancestral forms of 
Ratite, —if they could be shown really to have Struthious affinities it 
would be a simple matter to connect them and the modern hea with 
Diatryma from the Eocene of New Mexico ; further, with the Tertiary an- 
cestors of Struthiolithus, Struthio proper, and the moas of New Zealand ; 
and perhaps finally with the little known Gastornithide from the London 
and French Eocene. Indeed, much stress was laid by Lyddeker on the 
resemblances between Gastornis and the leading genus of the Stereor- 
nithes, Phororachos. But however attractive such a theory might seem 
at first glance, we are obliged to renounce it as illusory in view of recent 
destructive criticisms at the hands of such excellent anatomists as F. A. 
Lucas, C. W. Andrews, and others, who have caused even Ameghino 
and Lyddeker to recede from their original opinions. 

The last named author,! writing in 1893, placed Gastornis, Brontornis, 
and Phororhachos unhesitatingly among the atite, as the latter are 
commonly understood. He refers to “the modern German [ Firbring- 
er’s] view that the Ratite form a compound group, of which the 
various sections have been independently derived from several perfectly 
distinct Carinate ancestors, and that their mutual resemblances to one 
another are solely owing to the effects of adaptation”; but his own 
personal opinion is expressed in the following words: “I confess, 
however, that the supposed Anserine affinities of Gastornis appear far 
from clear to me, while I always feel that the great difficulty in admitting 
the multiple origin of the Ratite is that, if this had been the case, there 


1 Lyddeker, R., On the Extinct Birds of Argentina (Ibis, [6], Vol. V. pp. 46, 47). 
1893. 


EASTMAN: REMAINS OF STRUTHIOLITHUS CHERSONENSIS. 137 


would have been far less structural similarity to one another among the 
various groups than we find to prevail.” 

Dr. Ameghino’s final conclusion is that the Stereornithes appear to 
show that the division of the class of birds into Ratite and Cartnate is 
not fundamental, —a view which has been especially advocated by Mr. 
Lucas among American ornithologists. The latter," in a critical review 
of Ameghino’s work, speaks as follows : ‘‘ Apparently the main reasons 
for comparing such forms as Phororhachos and Grontornis with the 
Struthiones is because they are large and extinct, when, as a matter of 
fact, mere size is no reason for supposing a bird related to an ostrich ; 
while the pelvis of Phororhachos, with its aborted pubis, shows that this 
genus at least is very many removes from any Struthious bird. Nei- 
ther is Gastornis, with its primitive type of skull, any relation of the 
Stereornithes.” 

Precisely the same attitude is displayed by Mr. Andrews,? who denies 
that the Stereornithes have anything in common with Struthious birds 


or with the Gastornithida, neither are they by any possibility descended 
from Hesperornis. Says he: “The Stereornithes seem to be a hetero- 
geneous group of birds in all of which the wings were reduced and the 
bulk increased through the operation of some peculiar local conditions ; 
for instance, the land which they inhabited may have been an island on 
which no large carnivorous animals occurred. A similar example is 
offered by New Zealand, where the Dinornithide, Apteryx, Aptornis, and 
Onemiornis (all flightless birds of large size, and belonging to distinct 
orders) were formerly found. Indeed, there seems to be no reason why 
at any time, from the late Secondary period onward, and in any region, 
similar groups of flightless birds might not have arisen under favorable 
circumstances. The Gastornithide may be another instance of such. 
In most cases such specialized races die out without leaving any descend- 
ants when the peculiar conditions to which they have become adapted 
pass away ; but the modern Ratite may be survivors of one or several 
ancient groups of such flightless birds.” 

Still more explicit are Mr. Lucas’s views as to the nature and origin 
of the so-called Struthious birds, which he defines as ‘ those generalized 
birds which through some special adaptation to their surroundings or 
freedom from enemies have been able to survive to the present day. 
Rhea and Struthio are typical examples of this. While it would be 


1 The Auk, New Series, Vol. XIII. (1896), pp. 62, 63. 


? Remarks on the Stereornithes, a Group of Extinct Birds from Patagonia 
(Ibis, [7], Vol. II. p. 12). 1896. 


138 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


assuming too much to say that the limit of size has been attained by 
any bird of flight, it is yet very evident that the difficulties of flight 
increase very rapidly with increase of size, — hence the correlation be- 
tween gigantic stature and loss of flight. It is a noteworthy fact that 
the forms attaining the maximum size in their respective groups are 
generally flightless, e. g. Cnemiornis, Notornis, Didus, ete. Since flight- 
less forms have originated in comparatively recent times wherever the 
conditions were favorable, so undoubtedly they arose in the past, and 
only amid unusually favorable conditions and stable environment could 
these ancient flightless forms persist. That existing ‘Ratite’ birds 
were long ago differentiated from the parent stock, or that they arose 
independently, is indicated by the great differences between forms sepa- 
rated by considerable stretches of water. In view of the parallel devel- 
opment of the horse and rhinoceros in Europe and America, it would 
hardly seem necessary to suppose a unity of origin for Struthious birds ; 
moreover the palzeontological history of the class is so fragmentary that 
phylogenetic arrangements of the birds can be regarded as little more 
than guesses. As to the characters of the Ratite, the absence of a keel 
to the sternum and the slight angle between the scapula and coracoid are 
purely degenerate features without the slightest taxonomic value; and 
the ‘ Ratite’ type of skull is a generalized skull having resemblances to 
that of the reptiles. The characters in which Hesperornis resembles the 
ostrich are generalized characters, such as one would be surprised not to 
find in so early a bird; its shoulder girdle is unique among birds and 
decidedly reptilian, while the foot is the most highly specialized swim- 
ming foot known. ‘That this bird is the direct descendant of any land 
bird is incredible. As for the tinamous, their skull and pelvis of a very 
generalized type prevents us from regarding them as recent derivatives ; 
they are in fact ‘ hold-overs’ in a region noted for the number of curious 
forms it contains, indicating the persistence of a few very old species in 
the midst of a more advanced yet not strictly modern fauna.” ? 

1 The above quoted remarks are from some notes which Mr. Lucas very kindly 
took the pains to write out by way of comment on the present paper before it was 
finally prepared for press; and the writer has great pleasure here in acknowl- 
edging his indebtedness to this source for many helpful criticisms and suggestions. 
Reference should be made also to Mr. Lucas’s review of Professor Thompson’s 
paper “On the Systematic Position of Hesperornis,” published in The Auk, Vol. 
VIII. p. 804 (1891), as well as to the comments of Dr. J. A. Allen in the same 
journal, Vol. XV. p. 70 (1898), which brings the literature of /esperornis down to 
date. For a copious bibliography of the distribution of recent birds, see Mr, P. L. 
Sclater’s address before the Second Ornithological Congress at Budapest, May, 
1891. 


EASTMAN: REMAINS OF STRUTHIOLITHUS CHERSONENSIS. 139 


Strong enough arguments, we think, have been put forward to show 
that the theory of a common origin of the Ratite is untenable, and 
hence no single hypothesis of distribution is able to account for the facts 
of their distribution. We cannot imagine a race of ostriches sprung 
from Hesperornis or anything of like nature in the Cretaceous, spreading 
over the whole earth in the Tertiary, and then, as decay set in, leaving 
its fragments scattered in remote corners of the globe. But the prob- 
lems presented by the alternative theory, that of multiple origin, are 
none the less interesting or important, althongh decidedly more compli- 
cated. To seek the nearest Carinate affinities for the different sections 
of Ratite separately ; to develop the palzeontological history of each 
more fully; and to inquire into the physical and biological conditions 
which led to their insulation, perpetuation, and differentiation in various 
provinces, — these are only a few of the points that invite an extended 
investigation. Some of the problems have already been touched upon, 
notably as regards the origin of the moas, the South American ostrich, 
and Apyornis ; and we may profitably turn our attention for a moment 
in this direction, beginning with Rhea. 

No one can deny that the physical resemblances between Ahea and 
Struthio are very great; in fact, the popular term “South American os- 
trich ” is an obvious commentary on their similarity. Although both 
genera are regarded as typical of distinct families, and are even com- 
monly placed in separate suborders, yet, if one were asked to specify the 
nearest living ally of the African ostrich, he would unhesitatingly point 
to Rhea. Only two interpretations of structural resemblances are pos- 
sible: either they indicate direct genetic relationships, or we have here 
a most remarkable case of convergence. Now in this instance we confess 
to sharing Dr. Lyddeker’s prejudice against the theory of parallel devel- 
opment, already quoted, as there is too striking a coincidence in the 
forms produced to be explained as the result of adaptation during recent 
times in two widely distant regions of the globe. The natural and only 
logical plan would be to assume blood relationship between J?he and 
Struthio as a matter of course, until it is proved that by no possibility 
could they have been derived from the same ancestral stock. Now if 
Rhea had different progenitors from the ostrich, we are in utter ignorance 
as to what they were like, as no other descendants remain. That there is 
anything in common between hea and the tinamous we cannot believe 
for a moment, in view of the different organization of the latter. Hence, 
Captain Hutton’s theory, which derives both Rhea and the moas from 
a tinamou-like ancestor which crossed into Australia and New Zealand 


140 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


by means of an imaginary Antarctic continent, must be relegated on 
both biological and geological evidence to the same category as the 
Lemurian hypothesis. 

Rhea still enjoys a comparatively wide distribution in South America, 
and its remains have been found in the bone caverns of Brazil. If the 
evidence of Diatryma in New Mexico means anything at all, it would 
point to a connection between a fossil North American and the existing 
South American ostrich. It is true that the late Tertiary yields no 
evidence of Struthious birds in North America. But it is also true that 
until the discovery of Struthiolithus under the shadow of the Great Wall 
in China, no one could have suspected the whole intervening territory 
between Northeastern Asia, South Russia, and Africa to have been in 
comparatively recent times inhabited by true ostriches. The palaonto- 
logical record is from the nature of things very deficient in the case of 
land birds, and many gaps can only be filled on indirect evidence. One 
such gap is now partially filled by the occurrence of Struthiolithus in 
Northern China. A race having the constitutional vigor and numerical 
force to establish itself in this latitude, — and in a mountainons region 
as well, where the struggle for existence is always intensified by a larger 
number of enemies than are found on the plains, to say nothing of the 
rigors of winter, — must have been able to penetrate still further north- 
ward, and might readily have accompanied-the mammals that migrated 
across the land bridge formerly connecting the palarctic and nearctic 
regions. 

In a word, if we can predicate any blood relationship between the 
African and South American ostriches, it is certain that the latter could 
have reached its present habitat in no other way than along the route 
marked by Struthio camelus, S. karatheodoris and S. asiaticus, Struthio- 
lithus, Diatryma, and the Rhea of Brazilian bone caverns. If any will 
presume to deny a relationship between Struthio and Mhea, they are 
confronted with these difficulties: to explain how two separate deriva- 
tives from Carinate birds should come to present such marvellons 
similarity to one another through the operation of purely fortuitous 
conditions, and to point out a lineage for Rhea connecting it more 
closely with Carinates than with the ancestors of Struthio. Sceptically 
inclined individuals are weleome to regard Rhea as one of the “ waifs 
and strays of a lost avifauna left by the sea of time stranded on the 
shores of the present,” but we personally prefer the more positive 
view, which connects the New and Old World ostriches in the manner 
indicated. 


EASTMAN: REMAINS OF STRUTHIOLITHUS CHERSONENSIS. 141 


Turning now to the advent of the moa into New Zealand, and of 
Apyornis upon the island of Madagascar, we note that previous writers 
have essayed in various ways to meet the following dilemma. If these 
birds migrated from what is now the mainland prior to the Tertiary, why 
have not their remains been found in strata older than the Pliocene ? 
Or, if the islands remained inaccessible to them until the late Tertiary, 
how was the passage finally accomplished by wingless birds? And what 
is still more to the point, why were they in the latter event unaccompa- 
nied by placental mammals? Of the two principal theories put forward 
to explain the facts, neither, in the opinion of the present writer, suffi- 
ciently accounts for all the difficulties. In the case of the moas, Mr. 
Wallace * supposes that their ancestors either flew or swam across straits 
impassable to contemporaneous mammals. But Captain Hutton prop- 
erly takes exception to this view, on the ground that their Ratite 
characters are due to their being unable to fly ; moreover, the oldest 
known moas were entirely without wing bones, and possessed a very 
rudimentary shoulder girdle. As to the alternative explanation that 
they crossed by swimming, Captain Hutton? remarks as follows: “ But, 
although the emeu and the rhea are both said to take readily to water, 
many placental mammals do the same, and it is very unlikely that the 
Struthious birds should twice have swum across the same straits — once 
from the Oriental to the Australian region, and again from the Austra- 
lian to New Zealand — which were impassable to mammals. There are 
also other reasons for doubting the northern origin of the Australasian 
Ratite.” 

Now, as most persons are aware, both biological and geological evi- 
dence go to show that New Zealand has been separated from Australia, 
and Madagascar from Africa, at all events ever since the dawn of the 
Tertiary, and probably since the latter part of the Cretaceous. Accord- 
ingly, Captain Hutton supposes, after having shown the improbability 
of wingless birds either flying or swimming across straits, that the moas 
have had a different origin from the rest of the Ratite,—an opinion 
from which we find no reason to dissent, although rejecting his hypothe- 
sis of a tinamou-like ancestor in the Eocene, and a submerged Antarctic 
continent. Although the oldest known remains of the Dinornithide are 
of Miocene age, and no one has attributed to the family an earlier origin 
than the Eocene, yet the occurrence of moa remains on the continent of 


1 Wallace, A. R., Island Life, 2d edition, p. 481, 1892. 
2 Hutton, F. W., The Moas of New Zealand (Trans. New Zealand Inst., Vol. 
XXIV. p. 147), 1891. 
VOL. XXXII. — NO. 7. 2 


142 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


Australia (Pliocene of Queensland) furnishes ground for believing that 
a form of wingless bird arose in Australasia at some time previous 
to the detachment of the present New Zealand and adjacent islands 
from the mainland. If the stock really had an uninterrupted Tertiary 
history, it is of course immeasurably removed from any existing Carinate 
forms, or other Ratite. The moas are supposed to have enjoyed their 
period of culmination during the Pliocene, when they flourished prodi- 
giously and covered the land, but thereafter they suffered great mortality. 
Their extinction was certainly not caused by the encroachment of natu- 
ral enemies, any more than was the case with Zpyornis ; nor can their 
decline be reasonably attributed to physical or climatic changes of which 
we have no evidence. Their decadence not being traceable to external 
influences, we can only interpret it as the result of some inherent cause 
or causes, — taken together with the retarded action of natural selec- 
tion, — such as are frequently seen to follow in the wake of hypertrophy 
among various groups. 

We cannot pass from this subject without calling attention to Captain 
Hutton’s remarkably ingenious explanation of the crowding together of 
so many varieties of Struthious birds in the limited area of New Zea- 
land, and the unequal distribution of species between the two islands. 
What appear at first sight to be unparalleled or anomalous features of 
distribution are all consistently explained on the theory of a simple 
order of geographical changes, namely, alternating elevation and subsi- 
dence of land masses. ' Two periods of subsidence and one of elevation 
are sufficient to account for all the phenomena, according to Captain 
Hutton’s hypothesis. His interpretation, with which Mr. Wallace 
heartily concurs, is concisely summarized by the latter author as fol- 
lows: “First, we must suppose a land connection with some country 
inhabited by Struthious birds, from which the ancestral forms might be 
derived ; secondly, a separation into many considerable islands, in which 
the various distinct species might become differentiated ; thirdly, an 
elevation bringing about the union of these islands to unite the distinet 
species in one area; and fourthly, a subsidence of a large part of the 
area, leaving the present islands with the various species crowded 
together.” ! 

To revert finally and in few words to the origin of 2pyornis, it is plain 
that, if its ancestors reached the island from Africa as flightless birds, 
the migration must have taken place not later than the Eocene, since no 
mammals initiated since the Cretaceous are found in Madagascar. The 


1 Loc. cit. p. 479. 


EASTMAN: REMAINS OF STRUTHIOLITHUS CHERSONENSIS. 143 


lemurs, insectivora, rodents, and reptiles now inhabiting the island bear 
the stamp of great antiquity. It is true that Zpyornis remains, so far 
as known, are confined to deposits of supposed Pleistocene age, and the 
material itself is inconsiderable.'| The deficiency may be partially ac- 
counted for owing to lack of exploration, and imperfection of the pale- 
ontological record, especially as concerns land birds. But if it be 
objected that a continuous Tertiary history implies a higher degree of 
specialization and greater specific variation than we have any evidence 
of, we must not forget that here the action of natural selection was 
more or less suspended, owing to the abundance of food, absence of 
carnivorous or other powerful enemies, and generally mild conditions. 
The same causes produced the same effects upon the ancestors of py- 
ornis as upon the moas, of which Captain Hutton affirms, ‘“ Under such 
favorable circumstances the conditions of life were very easy, and the 
birds grew larger and fatter, more sluggish and more stupid,” — until, 
in fact, they became effete and were finally extirpated. 

On the assumption that the forerunners of Zpyornis have inhabited 
Madagascar ever since its separation from the mainland, it is not surpris- 
ing that this genus should have to stand by itself as the representative 
of a distinct suborder. Some resemblances to the Struthio-Rhea branch 
of the Ratite are observable, to be sure, — even the egg shells having a 
remarkably similar structure, as shown by Nathusius, — and anatomists 
like Firbringer, Milne-Edwards, and Grandidier have endeavored to 
show even greater similarity to Dromeus and Casuarius, which are 
regarded as the most primitive of existing Ratite. But all are agreed 
that the differences far exceed the resemblances, being in fact funda- 
mental. To us it seems that the amount of divergence from other 
known types, living and fossil, coupled with the slower rate of variation 
affectiug insular forms, and, above all, the generalized characters ob- 
served in Apyornts, go to show that this bird is far from being a modern 
derivative, but is the last of a very ancient race. We see no impropri- 
ety in supposing that its flightless ancestors inhabited the Madagascar 
region when it was still a part of Africa, and that other descendants 
may have migrated northward into Europe during the early Tertiary. 


1 Andrews, C. W., Note on a nearly complete Skeleton of Zpyornis from Mad- 
agascar (Geol. Mag., Dec. 4, Vol. IV. pp. 241-250), 1897. Burckhardt, R., Ueber 
pyornis (Palaeont. Abhandl. Dames und Kayser, Vol. II. Heft 2), 1893. 


144 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


DESCRIPTION OF THE PLATE. 


Fig. 1. Struthiolithus chersonensis Brandt. From superficial deposits in the neigh- 
borhood of Kalgan, China. Obverse, or more weathered aspect, with 
prominent pittings. X §. 

Fig. 2. Reverse aspect of same specimen, showing uncorroded areas. Millimeter 
scale at bottom of the figures. X 3. 


(Reproduced from photographs by Mr. C. H. Currier, of Boston.) 


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Bulletin of the Museum of Comparative Zoology 
AT HARVARD COLLEGE. 
VoL. XXXII. No. 8. 


REPORTS ON THE DREDGING OPERATIONS OFF THE WEST COAST OF 
CENTRAL AMERICA TO THE GALAPAGOS, TO THE WEST COAST 
OF MEXICO, AND IN THE GULF OF CALIFORNIA, IN CHARGE OF 
ALEXANDER AGASSIZ, CARRIED ON BY THE U. §S. FISH COMMIS- 
SION STEAMER ‘“ ALBATROSS,” DURING 1891, LIEUT. COMMANDER 
Z. L. TANNER, U. S. N., COMMANDING. 


XXIV. 


PRELIMINARY REPORT ON BRANCHIOCERIANTHUS URCEOLUS, 
A NEW TYPE OF ACTINIAN. 


By E. L. Marx. 
[Published by Permission of MARSHALL MCDONALD and GEORGE M. BOWERS, 


U.S. Fish Commissioners. | 


Wirth THREE PLATES. 


CAMBRIDGE MASS. U.S. A.: 


PRINTED FOR THE MUSEUM. 
Avaust, 1898. 


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No. 8. — Report on the Dredging Operations off the West Coast 
of Central America to the Galapagos, to the West Coast of Mex- 
ico, and in the Gulf of California, in charge of ALEXANDER 
Aaassiz, carried on by the U. S. Fish Commission Steamer 
“ Albatross,” during 1891, LizuT. COMMANDER Z, L. TANNER, 
U.S. N., Commanding. 


XXIV. 


Preliminary Report on Branchiocerianthus urceolus, a new Type of 
Actinian. By E. L. Marx." 


OnE of the most interesting of the many new forms brought up in the 
dredgings of the Albatross Expedition under Mr. Agassiz in 1891 was a 
deep-sea actinian which bore so strong a resemblance to Cerianthus in 
its general appearance that the sketches made at the time are marked 
“new Cerianthus.” An examination of the superficial characters shows, 
however, as Mr. Agassiz (’91, p. 187) at once recognized, that this new 
form differs in important points from the genus Cerianthus, and may 
indeed require the erection of a new family for its reception. Its two 
most striking morphological features are a pronounced bilateral sym- 
metry and the possession of an incomplete circle of branching gill-like 
organs. The latter peculiarity I utilize in proposing for it the new 
generic name Dranchiocerianthus. 

A considerable number of specimens were taken at each of two hauls 
in the Gulf of Panama, not far from Cape Mala, at Stations 3385 and 
3389, the depths being respectively 286 fathoms and 210 fathoms, and 
the bottom being in both instances green mud. The colors, as shown by 
the colored sketches drawn at the time by Mr. Westergren, were brick- 
red for the column, deep carmine for the marginal tentacles, and rose- 
pink for the oral disk, and all the structures arising from it, including 
the oral tentacles. The specimens were all preserved in strong alcohol. 


1 Contributions from the Zodlogical Laboratory of the Museum of Comparative 
Zodlogy at Harvard College, E. L. Mark Director, No. XCIII. 
VOL. XXXII. — NO. 8. 


148 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


The animal as sketched in the fresh condition by Mr. Agassiz consists 
of a vase- or pitcher-shaped “ flower” surmounting a long stalk, from 
which it is clearly marked off by a broad shallow constriction. The 
outlines are extremely graceful, presenting in front and back views 
(Plate 1) a symmetrical vase-like figure with flaring lips. A side view 
(Plate 2) shows that one margin of the disk is much higher than the 
other, so that in this aspect the upper end of the animal resembles the 
lip of a broad-mouthed pitcher. ‘The disk, when spread by pinning out 
the marginal tentacles, has an oval outline; but in the natural state the 
lateral margins of the disk are folded in symmetrically from either side, 
so as almost to touch at a point a little below the middle of the oval. 
This bending in of the margins of the disk produces at the upper end of 
the animal a sort of eccentric funnel-shaped depression, which, however, 
does not lead to the mouth opening, but to the outside again, at the 
lower margin of the oral disk. The fancied resemblance of the animal 
to a little pitcher, which this side view presents, has suggested the 
specific name adopted, — urceolus. 

In this actinian we may recognize two fairly well marked regions, — 
the “flower” or calyx and the stalk. The former embraces the upper 
part of the column in addition to the disk proper and its appendages ; 
the latter is the remaining part of the column with its swollen base. A 
slight and somewhat oblique constriction, often emphasized by a con- 
spicuous line, indicates, the place of transition from one to the other. 

The oral disk is so modified in form as to bear little resemblance to 
that of Cerianthus. When in preserved specimens the marginal ten 
tacles are pinned out under slight tension, the disk has, as already 
stated, an oval outline, the longitudinal and transverse diameters of 
which in the specimens measured range between 25 mm. (longitudinal) 
by 15 mm, and 38 mm. by 30 mm. The surface of the disk is very 
oblique to the longitudinal axis of the column. The marginal ten- 
tacles are interrupted at the edge of the disk nearest the base. This 
edge I shall, for convenience, designate as posterior, the opposite pole of 
the long axis of the disk anterior. I adopt these designations without 
the intention of advocating now any of the theoretical views concerning 
the broader questions of comparative morphology in Actinozoa, 

The marginal tentacles have a deep carmine color in the living animal, 
becoming in alcohol a dark maroon or claret color; they vary in number 
from 85 to 97. Iam not yet certain that there is an unpaired anterior 
tentacle, as in Cerianthus, but believe it probable that there is, because 
there are usually an uneven number of tentacles, and the method of 


MARK: BRANCHIOCERIANTHUS URCEOLUS. 149 


their formation is apparently the same as in Cerianthus. They are sym- 
metrically arranged at the margin of the disk, the hiatus at the posterior 
margin giving the line which connects their several insertions the form 
of an elongated horseshoe. The shortest, and evidently youngest, ten- 
tacles occupy the ends of the two arms of the horseshoe, and are there- 
fore near the posterior margin of the disk; but the tentacles do not 
increase regularly in length toward the anterior margin. There are 
usually one or two pairs of posterior tentacles that are quite short ; 
but the two of a pair are not necessarily of equal length ; the more an- 
terior ones are successively longer and longer until a maximum length 
of abont 125 mm. (in alcoholic material) is reached in about the tenth 
pair from the posterior margin. From this region forward there is a 
gradual and not great diminution in the length of the tentacles up to 
and including the anterior ones. This gives to the whole disk with its 
marginal tentacles, when pinned out, an appearance somewhat resembling 
acommon palm-leaf fan. The marginal tentacles are so crowded that 
they are much flattened at their bases, and overlap one another, as 
shown in the figure on Plate 3; but the shorter tentacles near the 
posterior margin of the disk (one or two pairs) are usually separated 
from the next more anterior ones by an appreciable distance. 

The middle region of the disk is raised into a nearly cylindrical oral 
tube, which in cross section is oval, and bears at and near its summit 
the oral tentacles ; below these there is usually a slight constriction. The 
free end of this oral tube occupies a plane perpendicular to the long axis 
of the column, i.e. it is not oblique, like the disk from which it rises. 
Owing to the obliquity of the disk to this axis, one side of the oral tube 
— the posterior — is much longer than the opposite side. For the same 
reason the posterior face of the oral tube passes almost imperceptibly 
into the disk whereas the lateral and especially the anterior faces 
make with the disk an angle. Viewed from the upper end, the oral tube 
in the fresh specimen presents an oval outline, the oval being nearly 
twice as long in the antero-posterior direction as in the transverse. 
There is no marked difference between the two angles of the mouth; but 
sections may disclose the presence of a siphonoglyph. The oral tentacles 
outnumber the marginal ones, there being about 130 of them. They are 
arranged roughly in quincunx, and occupy four or five rows on the outer 
surface of the upper end of the oral tube. They vary in size, the largest 
being (in alcoholic material) about 30 to 35 mm. in length, and 0.5 mm. 
in diameter at the base. These, too, are so crowded as to be much 
flattened at their origin. 


150 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


From the oral disk immediately outside the base of the oral tube 
there arises a row of branching thin-walled organs, which are probably 
to be regarded as gills. Like the marginal tentacles, this row of gills is 
interrupted at the posterior side of the disk, and consequently has the 
form of a horseshoe. There are usually 16 pairs of gills and an odd 
one, making 33 in all; but in one specimen there were only 27 in all, 
and in another there were 37. Mr. Agassiz has sketched one individual 
with only 21. There is considerable variability in the size of the gills; 
the posterior ones, though usually smaller than the anterior ones, are not 
always so. A few small gills are sometimes intercalated between those 
of larger size. Though arranged approximately in a single row, there is 
some irregularity in their position, especially toward the anterior end of 
the disk, where they are more crowded than near the posterior end. In 
fresh specimens they are of a rose-pink color, but in alcohol this color is 
lost. 

Each gill consists of a single cylindrical, or somewhat flattened hol- 
low stalk, terminating in quite regular dichotomously forking branches. 
The stalk rises abruptly from the surface of the disk, sometimes being 
slightly constricted at its base; it has a length of from 4 mm. to 
8 mm., and a fairly uniform diameter of from 0.5 mm. tol mm. The 
forking may extend to the production of branches of the ninth or tenth 
order. The terminal branches, of which there may be nearly 500 toa 
gill, end blindly with rounded tips. In alcoholic material the branches 
are often varicose, owing to distention with coagulated contents. In 
the living condition they are probably of much more nearly uniform 
calibre. When not contracted the gills rise above the oral orifice, and 
even above the oral tentacles themselves. 

Radial canals are traceable running across the disk from the base of 
the oral tube to the bases of the marginal tentacles, before reaching 
which many of them fork, each of the branches communicating with the 
lumen of a single tentacle. 

The outer surface of the calyx constitutes the upper part of the 
column; its height is greatest in front, diminishing to practically zero 
behind. Above the constriction which marks the transition from it to 
the stalk proper, it gradually expands to meet the margin of the oblique 
oral disk. It is marked with fine longitudinal dark lines alternating 
with lighter ones, as in the rest of the column. 

The column resembles that of Cerianthus in being elongated, eylindri- 
cal, and enlarged at its basal end. Below the constriction which marks 
the boundary of cup and stalk it presents a spindle-shaped enlargement. 


MARK: BRANCHTOCERIANTHUS URCEOLUS. Pi 


In the alcoholic specimens. which I have measured the stalk below the 
constriction varies from 105 mm. to 200 mm. in length, and from 3 mm, 
to 5 mm. in diameter. The enlarged bulb-like end is from 6 mm. to 
8 mm., or even more, in diameter. But in preserved specimens the 
stalk is much folded lengthwise, so that the direct measurement of its 
diameter is not reliable. A portion of the stalk of a medium sized indi- 
vidual cut out, slit open lengthwise, and pinned out, measured 22 mm., 
so that the corresponding diameter would be about 7 mm. The bulbous 
enlargement reaches about twice that diameter. The column is smooth, 
except for very minute appendages at the basal end, and marked by 
narrow longitudinal brownish lines about 0.2 mm. broad, alternating 
with lighter colored brownish or buff ones about three times as wide 
(0.6 mm.). The darker lines in the fresh specimen are bright brick-red. 
Individuals differ much in the depth of color, which in all is less in the 
bulbous region, where the distinction between the light and dark lines 
almost disappears. The wall of the stalk, though not very thick, is quite 
rigid ; that of the bulb is somewhat thinner. The bulb terminates in 
a small, nipple-like elevation ; but a terminal pore, if present, must be 
very minute, for I have been unable to detect one by examination of 
specimens in toto. The bulb often contains a large quantity of the 
shells of Foraminifera. 

The outer surface of the lower part of the bulb is provided with small 
tapering filamentous appendages, which are 50 to 75 in diameter at 
their bases, but diminish abruptly to less than half that diameter and 
then taper gradually to a point. They vary in length from 0.5 mm. to 
1 mm., rarely more in alcoholic material, and are rather evenly distrib- 
uted over the surface at distances of 0-5 or 0.3 mm. apart ; but they are 
not arranged in any definite pattern. They remind one of the peculiar 
appendages of the egg shell in Fundulus heteroclitus, especially of those 
of the half grown ovarian eggs (cf. Eigenmann, 790, Plate I. Fig. 6). 

The lower end of the column, its bulbous enlargement, is invested 
by a case which extends upward at least for a tenth of the length of the 
column, and is open at its lower end. It is, of course, the secreted 
product of the lower and of the column, but it has a more complicated 
structure than is common in sheath-inhabiting actinians. In an indi- 
vidual whose stalk was 200 mm. long the case was about 25 mm. long, 
exclusive of the peculiar hair-like appendages which it bears. The 
lower three fifths of the case differs from the upper two fifths in possess- 
ing very numerous long hair-like hollow appendages. The upper two 
fifths may be divided into two zones of about equal breadth. The secre- 


152 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


tion of the upper zone is simply corrugated and folded longitudinally ; 
that of the lower exhibits thickened patches a millimeter or more in 
diameter and fairly closely set. Of these patches there are three or four 
rows running around the column. The secretion of all three regions has 
a fibrous appearance due to the fine, sinuous corrugations which run 
around the column, and are the expression of differences in the thickness 
of the secretion. The effect is as though the secretions had been formed 
as rings, more or less complete, which had been crowded downward by 
successive additions above. In the region which bears the hairs the 
same appearance is shown, under a low magnification, by the secretion 
which constitutes the hair. This is a hollow thin-walled cylinder, which 
gradually diminishes in size from its base, where its diameter is about 
0.2 mm., to its free end. The hairs attain a length of 25 mm. or more, 
and are so tough that they form for the actinian a means of secure 
anchorage in the mud. The corrugations of the wall of the hair which 
run around it are not due to folds of the secreted substance, for optical 
longitudinal sections of the hairs show that the inner surface of the tube 
is smooth. When the animal is thrown into alcohol this case, with its 
tuft of matted hairs, is readily detached from the column, but a careful 
examination of those case secretions which are not thus artificially sepa- 
rated shows that there are at intervals exceedingly minute filaments 
running out from the surface of the animal to the inner surface of the 
case, and I am convinced that these are the minute filaments described ~ 
as arising at regular intervals from the surface of the bulbous portion 
of the column. I believe that a single filament is enclosed in each of | 
the hollow hair-like appendages of the case, and that the form and size 
of these hairs is, in part at least, determined by the presence and shape 
of the filaments of the column. The lower part of the case is much 
wrinkled lengthwise, and projects to some distance (5 or 10 mm.) below 
the base of the column. It has the appearance of having once sur- 
rounded the enlarged end of the column and having been slipped back- 
ward, its elasticity causing it to become wrinkled like the mouth of a 
meal-sack that is tied. The hair-like processes surround this open end 
of the case and project beyond it. 


eo 


MARK: BRANCHIOCERIANTHUS URCEOLUS. 15 


PAPERS CITED. 


Agassiz, A. 

91. Three Letters from Alexander Agassiz to the Hon. Marshall McDonald, 
United States Commissioner of Fish and Fisheries, on the Dredging 
Operations off the West Coast of Central America to the Galapagos, ete. 
Bull. Mus. Comp. Zodl. Harv. Coll., Vol. 21, No. 4, pp. 185-200. June. 


Eigenmann, C. H. 
90. On the Egg Membranes and Micropyle of some Osseous Fishes. Bull. 
Mus. Comp. Zodl. Harv. Coll., Vol. 19, No. 2, pp. 129-154, Pls. 1-3. 
March. 


154 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


EXPLANATION OF PLATES. 


The drawings are by Magnus Westergren, from sketches by Alexander Agassiz. 


PLATE 1. 


Upper end of Branchiocerianthus urceolus, seen from the side (posterior) bearing 
the youngest marginal tentacles. Fresh specimen. Magnified 21. 


PLATE 2. 


Side (slightly oblique) view of same. 


PLATE 3. 


Upper end of an alcoholic specimen of same, viewed from the same side as in 


Plate 1, but as it appears when the tentacles are pinned out so as to expose the 
surface of the oral disk. 


Atpatross Ex, 1891. BRANCHIOCERIANTHUS. PLATE 1. 


A.M. Westergren del, Folsom & Sunergren photo. 


BRANOCHIOCERIANTHUS. PLare 2, 


ALBATROSS Ex, 1891. 


Folsom & Sunergren photo, 


A.M. Westergren del, 


BRANCHIOCERIANTHUS. PLATE 3. 


ALBatross Ex. 1891. 


Folsom & Sunergren photo, 


A.M. Westergren del. 


Bulletin of the Museum of Comparative Zodlogy 
AT HARVARD COLLEGE. | 
VoL. XXXII. No. 9. 


ACALEPHS FROM THE FIJI ISLANDS. 


By ALexaNDER AGASSIZ AND ALFRED GOLDSBOROUGH MAYER. 


Wits SEVENTEEN PLATES. 


CAMBRIDGE, MASS., U.S. A.: 
PRINTED FOR THE MUSEUM... 


Fesruary, 1899. 


No.9.— Acalephs from the Fiji Islands. By ALEXANDER 
AGassiz and ALFRED GOLDSBOROUGH MAYER. 


INTRODUCTION. 


Dorine a visit to the Fiji Islands, extending from November 7, 1897, 
to January 13, 1898, we devoted considerable time to a study of the 
Marine pelagic fauna. We made use only of open tow-nets, and while 
the majority of our hauls were made upon the surface, a number were 
also made at depths varying from twenty-five to one hundred fathoms. 
Most of these deeper hauls were made at a station three to five miles 
south of the entrance of Suva Harbor, and it was remarkable that the 
tows drawn from one hundred fathoms were far richer, both in number 
and variety of species, than were those made at twenty-five to fifty 
fathoms. No precise conclusions can, however, be drawn concerning the 


*bathymetrical distribution of marine organisms from these results, for, 


owing to the fact that the mouth of the tow-net was constantly open, 
we cannot state the depth from which any given animal may have come ; 
and, moreover, the near proximity of the land, and the extremely com- 
plex currents and eddies that are so characteristic of this region of 
Coral Reefs, probably play a far more important part in the distribution 
of pelagic organisms than does the mere fact of depth. The breakers 
are constantly forcing the ocean water over the reefs into the shallow 
lagoons, from which it finds access again into the sea through the 
openings in the walls of the reef, so that in some instances one finds a 
strong current, that is in great measure independent of the tide, con- 
stantly flowing outward from the lagoon into the open ocean. Such 
currents acting in conjunction with the tidal flow cause extensive eddies 
that result in a very ununiform distribution of pelagic life. 

Besides our hauls in the neighborhood of Suva we made others off 
Taviuni, Kimbombo, Vanua Mbalavu, Ngamia, Wailangilala, Totoya, 
Mbatiki, Kandavu, and Nukulau Islands. The hauls were rich in 
Crustacea, but deficient in the number of Worms, Echinoderm larvee, 


and Medusz. Indeed, our success was remarkably inferior when com- 
VOL. XXXII. —NO. 9. 1 


158 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


pared with what we should expect to find in the sub-tropical regions of 
the Atlantic Gulf Stream. We obtained seven genera of Scyphomedusa, 
twenty of Hydromeduse, nine of Siphonophore, and two Ctenophoree. 
With the exception of two Rhizostome, all of the genera are repre- | 
sented by species found in the Atlantic Ocean. Indeed, the affinity 
between the Medusee of the Fiji Islands and those of the West Indies is 
remarkably close, and in six cases we are unable to distinguish any 
j 


specific differences between the Fijian species and well known Atlantic 
forms, and therefore venture to assert that they are specifically identical. 

The following table illustrates the Atlantic distribution of these Medusze / 
that are found also in the Fiji Islands. 


Halitiara formosa, Fewkes. Dry Tortugas Islands, Florida. 
Pandea violacea, nov. sp. Dry Tortugas Islands, Florida. 
Rhegmatodes floridanus, L. Agassiz. | Bahamas, Gulf of Mexico. ; 


/Hginella dissonema, Haeckel. Canary Islands; Dry Tortugas 
Islands. 


Agalma Pourtalesii, nov. sp. Dry Tortugas Islands, Florida. 


Abyla (Abylopsis) quincunx, Chun. Tropical Atlantic, Dry Tortugas 
Islands, Florida. 


In the following ten genera the Fijian form is represented in the 
Atlantic Ocean by a very closely allied species: Linerges, Nausithoé, 
Tamoya, Cunina, Aglaura, Gonionemus, Mitrocoma, Tiaropsis, Eutima, 
and Spheronectes. Indeed, the acalephan fauna of the Fiji Islands, 
if one excepts the Rhizostome, is more closely related to that of the 
Dry Tortugas Islands, Florida, than is the latter to the fauna of the 
Mediterranean Sea. 

In this connection it is interesting to notice that A. Agassiz’ has 
shown that the deep sea fauna of the Gulf of Mexico and the Caribbean 
Sea is far more closely allied to that of the Pacific than it is to that of 
the Atlantic, and this is accounted for upon the supposition that before 
the Cretaceous period the Gulf of Mexico and the Caribbean were in freer 
communication with the Pacific than with the Atlantic. Again, in ~ 
1892,? the same author found that in nearly all the groups of deep sea 

« 


1 Agassiz, A., 1883, Mem. Mus. Comp. Zodl., Vol. X. pp. 79-84. 
2 Agassiz, A., 1892, Bull. Mus. Comp. ZodL, Vol. XXIIL pp. 74-82. 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 159 


Fishes, Crustaceans, Mollusks, Worms, Echinoderms, and Polyps dredged 
off the west coast of Central America there were familiar West Indian 
types, or east coast forms. 

A recent survey of the region of the Isthmus of Panama has been 
made by Hill,’ who considers that it is impossible to make any serious 
deductions concerning the relations of North and South America during 
epochs preceding the Jurassic period, owing to the lack of data. He 
also concludes (p. 261) that the waters of the Atlantic‘and Pacific were 
probably as completely separated by a great continental land barrier in 
Cretaceous times as they are to-day, a proposition fully as tenable as the 
opposite hypothesis that they were united. If the marine passage ever 
existed across the Isthmus of Panama, or elsewhere in Tropical America, 
it must have been during the later Eocene period, and this strait was 
probably of a shallow and restricted character, and had finally disap- 
peared before the close of the Miocene period. 

If straits of considerable width and depth have ever connected the 
waters of the Tropical Atlantic with those of the Pacific, it is probable 
that the great Equatorial current would pour through them from the 
Atlantic into the Pacific, and thus the Pacific Ocean would become im- 
pregnated with Atlantic species. Once having gained access to the 
Pacific, the westerly Equatorial set would soon distribute the pelagic 
animals widely over the ocean. 

It is interesting to notice that while so many characteristic types of 
Tropical Atlantic Meduse are also found in the Pacific, the most emz- 
nently characteristic Tropical Pacific genera, the Rhizostome have re- 
markably few analogues in the Atlantic.? This, indeed, is what we 
should expect as a result of the westerly set of the great Equatorial 
current that would freely sweep animals from the Atlantic into the 
Pacific, but would in like measure hinder the entrance of Pacific forms 
into the Atlantic. 

Of the thirty-eight species of Acalephs found by us in the Fiji Islands, 
twenty-six are new to science. 


1 Hill, R. T., 1898, The Geological History of the Isthmus of Panama, ete. 
Bull. Mus. Comp. Zo6l., Geological Series, Vol. XXVIII. No. 5, pp. 151-285, 
Plates I—XIX. 

2 In this connection, see Lendenfeld, R. von, 1884, The Geographical Distribu- 
tion of Australian Scyphomeduse, Proc. Linn. Soc. New South Wales, Vol. IX. 
pp. 421-433. Also, Vanhdffen, E., 1888, Bibliotheca Zool., Bd. I. Heft 8, p. 46, 
Map. 


160 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


DESCRIPTION OF SPECIES. 


I. HYDROMEDUSZ. 


Halitiara formosa, Fewxes. 


\ 
Halitiara formosa, FEwxes, J. W., 1882, Bull. Mus. Comp. Zodl., Vol. IX. p. 276, 
Plate IV. Fig. 2. 


This Medusa is found in both Atlantic and Pacific Oceans. It is exceedingly 
abundant throughout the summer at the Dry Tortugas Islands, Florida, and 
we also found it in considerable numbers late in December in Suva Harbor, 
Viti Levu Island, Fiji Islands. The entoderm of the proboscis and tentacle 
bulbs of the male is usually dull brown or drab, while in the female it is bright 
green. 


Pandea violacea, nov. sp. 


This Medusa is common throughout the summer at the Dry Tortugas Islands, 
near the entrance to the Gulf of Mexico. We also obtained several specimens 
in Suva Harbor, Fiji Islands, early in January, 1898. We hope soon to pre- 
sent a figure of the Medusa in a paper upon “ Medusz from the Dry Tortugas,” 
that is to be published in the Bulletin of the Museum of Comparative 
Zodlogy. At present we will content ourselves with a description of the 
animal. ' 

Generic Characters. Pandea, Lesson, 1843. Tiaride with numerous tenta- 
cles, 8-16 or more arranged in a single row. The outer surfaces of the tentacle 


bulbs bear ocelli. There is no peduncle to the proboscis. The upper edges ~— 


of the proboscis are bound to the 4 radial tubes by means of 4 mesenteries. 
There are 4 simple gonads, with smooth outer surface. 

Specific Characters. The bell is 4 mm. in height, and is pear-shaped. The 
bell walls are of only moderate thickness. There are 32 tentacles. Eight of 
these are large, being about three times as long as the bell height ; and 24 are 
rudimentary. The bulbs of the large tentacles are hollow. Each and every 
tentacle bulb bears a single ocellus, making in all 32 ocelli. The velum is 
well developed. The proboscis is flask-shaped, its proximal portion being dis- 
tended by the 4 genital glands. The lips are simple and cruciform. There 
are 4 straight radial tubes and a broad circular tube. The color of the ento- 
derm of the proboscis and tentacle bulbs is delicate pink or light purplish 
brown. A green streak runs along the outer surface of the entoderm of each 
of the 4 radial canals. The ocelli of the tentacle bulbs are purple in color. 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 161 


Pennaria vitrea, nov. sp. 


Plate 1, Figs. 1, 2. 


Generic Characters. Pennaria, Goldfuss, 1820. Four rudimentary marginal 
tentacles that are rednced to mere basal bulbs. No ocelli. Four radial tubes. 
Gonads within the proboscis. No peduncle nor oral appendages to the 
proboscis. 

Specific Characters. The bell is 3mm. in height ; and the walls are thick 
and rigid. There are 4 rudimentary tentacle bulbs. The velum is not promi- 
nent. The 4 radial canals are straight and narrow. The proboscis in the 
female specimen (Fig. 1) was retracted within the cavity of the bell, but in the 
male (Fig. 2) it was flask-shaped, and projected for a little distance beyond 
the velar opening of the bell. These conditions, however, may be merely 
different states of contraction and not constant differences ; but, as we observed 
only two individuals, one a male and the other a female, we cannot be certain 
upon this point. The ova are large and pyriform, and are grouped in 4 radi- 
ally arranged clusters within the proboscis. The mouth opening of the pro- 
boscis is very simple, and there are no fimbriations or appendages. 

Prominent circular muscles were observed in the ectoderm of the cavity of 
the bell in the female, but these were not seen in the case of the male. It is 
possible, however, that they become apparent only during certain states of con- 
traction. In the female the ove and tentacular bulbs were flesh-colored, and 
the entoderm of the mouth of the proboscis was green. In the male the ten- 
tacular bulbs were green, the entoderm of the proboscis pink, and the lips 
green. 

Found off Kimbombo Island, November 25, and off Mbatiki Island, Decem- 
ber 5, 1897. 


Cytzis vulgaris, nov. sp. 
Plate 2, Figs. 3, 4, 5. 


Generic Characters. Cyteis, Eschscholtz, 1829. Margellide with simple 
unbranched oral tentacles upon the proboscis, and with 4 radially situated 
marginal tentacles. 

Specific Characters. ‘The bell is thin and slightly pyriform in shape, and is 
3mm. in height. The 4 marginal tentacles are somewhat stiff, and are usu- 
ally seen curled upward in a semicircular curve. The tentacle bulbs are large 
and prominent. The velum is well developed. There are 4 thin straight 
radial tubes. The proboscis (Figs. 3, 4) is pyriform, and possesses a slightly 
developed peduncle. Sixteen simple oral tentacles surround the mouth. The 
entodermal cells of these tentacle are disk-shaped, and their free ends are armed 
each with a battery of nematocysts (Fig.5). The mouth opening is simple, 
and, excepting for the oral tentacles, there are no other appendages. The color 
of the entoderm of the tentacle bulbs is dark salmon-red, as is also the entoderm 


162 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


of the proboscis near the peduncle. The remainder of the entoderm of the 
proboscis and of the tips of the marginal tentacles is green. 

Young Medusa. The youngest Medusa observed by us had only 4 oral ten 
tacles. The red color of the basal bulbs of the marginal tentacles extended for 
a considerable distance upward along the radial tubes. The bell was 1 mm. in 
height. 

This form is very abundant all over the Fiji Islands in November and De- 
cember. We came across a great swarm of these Meduse within the crater of 
Totoya Island. 


Bougainvillea fulva, nov. sp. 
Plate 2, Fig. 6. 


Generic Characters. Bougainvillea, Lesson, 1843. Margellide with dendriti- 
cally branching oral tentacles, and with 4 radially arranged bunches of mar- 
ginal tentacles. Proboscis wide and quadratic in cross section. Gonads 
developed in the ectoderm of the proboscis. 

Specific Characters. The bell is pyriform, and 2.5 mm. in height. The bell 
walls are of moderate thickness. There are 4 radially arranged bunches of 
marginal tentacles, each one of which consists of 3 tentacles. A dark pur- 
ple ocellus is found in the ectoderm of the tentacle bulbs at the base of each 
tentacle. The velum is well developed, There are 4 straight narrow radial 
canals. The proboscis is wide and quadratic in cross section. There are 4 
oral tentacles, each one of which branches dendritically twice. The gonads 
are found in the ectoderm of the proboscis. The entoderm of the tentacle 
bulbs and of the proboscis is flesh-colored. 

Single specimen, obtained in towing with an open net at 100 fathoms, three 
miles south of the mouth of Suva Harbor, December 16, 1897. 


Laodicea marama, nov. sp. 
Plate 3, Figs. 7, 8. 


Generic Characters. Laodicea, Lesson, 1843. Leptomedusze without otocysts, 
and with 4 simple unbranched radial canals, wpon which lie the gonads. Ten- 
tacles numerous. The tentacle bulbs are well developed, and many of them 
possess ectodermal ocelli. There are clubs and cirri upon the bell margin, 
between the tentacles. 

Specific Characters. The bell is quite flat and disk-shaped, and is 5.5 mm. in 
diameter. There are about 50 long, slender, flexible tentacles, each one of which 
possesses a well developed basal bulb. A single dark purple ocellus is found 
upon the inner side of the bulb of most of the tentacles. This ocellus is situ- 
ated in the ectoderm. There are numerous clubs and cirri (Fig. 8) between 
the tentacles. The velum is prominent. There are 4 narrow radial canals, in 
the upper portions of which, near to the proboscis, the gonads are found. The 
proboscis is short and slender, and the lips not prominent, The entoderm of 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 163 


the radial tubes and of the basal bulbs of the tentacles is opaque and slightly 
bluish in color. The entoderm of the proboscis is often green. 

This species is common in Suva Harbor in December. It is closely allied to 
Laodicea ulothrix, Haeckel, of the Canary Islands and Bahamas. 


Laodicea fijiana, nov. sp. 
Plate 3, Figs. 9, 10. 


Specific Characters. The umbrella is thin and bell-shaped, and 6 mm. in 
diameter. There are about 70 long, slender, marginal tentacles, the free ends 
of which are usnally coiled in a close helix. These tentacles are very fragile, 
and in the adult Medusa most of them are found to have been broken off near 
to the basal bulbs. In the young jelly-fish, however, they are usually seen ith 
a perfect condition. A single dark brown pigment spot, or ocellus, is found in 
the ectoderm on the inner side of the basal bulbs of about three quarters of the 
tentacle. There are no cirri between the tentacles, but there are about 8 clubs 
that occupy this situation. The velum is well developed. The lower portions 
of the 4 radial tubes, near to the circular canal, are straight and narrow; but 
their upper portions, near to the proboscis, exhibit complex diverticule. The 
gonads are situated upon this complexly developed portion of the radial canals; 
‘and in the female (Figs. 9, 10) the ova are prominent, and project outward in 
grape-like clusters over the surface of the genital organs. The proboscis is 
short and quadratic in cross section, and there are 4 well developed fimbriated 
lips. The entoderm of the proboscis and radial and circular canals is opaque 
and slightly blue in color. 

Common at Suva, Viti Levu Island, in December. 


\ 


Eutimeta levuka, nov. sp. 


Plate 9, Figs. 30, 31. 


’ Generic Characters. Eutimeta, Haeckel, 1879. Leptomeduse with 8 otocysts, 
and 8 tentacles, and with marginal cirri. The proboscis is borne upon a long 
peduncle. The gonads are found upon the 4 radial canals. 

Specific Characters. The bell is thin, and flatter than a hemisphere. It is 
8mm. in diameter. There are 8 well developed hollow tentacles. Four of 
these are about as long as the diameter of the bell, and the 4 others are only 
about one half of this length. Small lateral cirri (see Fig. 31) are found upon 
the sides of these tentacles. In addition to the large tentacles already described, 
there are 24 small papille upon the bell margin, and these are flanked by 
lateral cirri exactly as are the large tentacles. There are 8 otocysts, each one 
of which contains 3-5 otoliths. The velum is large. The 4 radial canals are 
straight and narrow, and the gonads are found upon them near to the circular 
vessel. The peduncle of the proboscis is slender, and 1} times as long as the 


164 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


diameter of the bell. The proboscis is flask-shaped, and there are 4 flanged 
lips. The genital organs, tentacles, and proboscis are slightly opaque and 
bluish in color. 

Several specimens, Suva Harbor, January, 1898. 


Staurodiscus nigricans, nov. sp. 


Plate 4, Figs. 11, 12. 


Generic Characters. Staurodiscus, Haeckel, 1879. Leptomeduse without oto- 
cysts, but with clubs between the tentacles. There are 4 radial canals, each of 
which gives rise to a pair of lateral canals. The gonads are situated upon the 
canals. ' 

Specific Characters. The bell is thin and flexible, and is 14 mm. in diameter. 
There are 12 short tentacles having well developed basal bulbs. Between each 
successive pair of tentacles there are 7 knot-like protuberances upon the bell 
margin, each one of which bears a sensory club. The velum is insignificant in 
size. Each of the 4 radial canals gives rise to a pair of lateral branches ; and 
thus 12 canals reach the circular vessel. The gonads are developed upon these 
canals (see Fig. 11). The proboscis is very short, and the mouth opening wide. 
The gelatinous substance of the bell has a brownish tinge. The genital organs, 
basal bulbs of the tentacles, and the proboscis are light sepia in color. The 
bulbs of the sensory clubs are dark brown. 

Single specimen, captured in an open tow-net that was drawn from 100 
fathoms, three miles south of the entrance of Suva Harbor, December 11, 
1897. 

This form differs from the two Atlantic species of Staurodiscus described by 
Haeckel (1879, Syst. der Medusen, pp. 145, 146) chiefly in that the side branches 
of the 4 radial canals reach the circular canal, whereas in the Atlantic forms 
they end blindly. 


Gonionemus suvaensis, nov. sp. 
Plate 5, Figs. 14-16. 


Generic Characters. Gonionemus, A. Agassiz, 1865. Trachomeduse, not 
Leptomeduse (see Haeckel, 1879, Syst. der Medusen, p. 146), with numer- 
ous sucker bearing tentacles that are all similar each to each. There are oto- 
cysts situated between the tentacles. The gonads are sinusoidally folded, and 
are situated upon the 4 radial canals. The proboscis is cruciform in cross sec- 
tion, and the lips are prominent. 

Specific Characters. The bell is flat and of moderate thickness. It is about 
three times as broad as it is high, and is 8 mm. in diameter. There are about 
70 long, stiff tentacles. The proximal portion of each tentacle is straight, but 
near the free end there is a small sucking disk, and beyond this the tentacle 
makes a sharp bend (see Figs. 14,15). There are about 16 otocysts, 4 in 


ee —_—” -. 


ee 


’ 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 165 


each quadrant. The velum is well developed. There are 4 straight radial 
tubes, upon the lower portions of which, near to the circular tube, the gonads 
are situated. The gonads are folded in a sinusoidal curve alternately to the 
right and Jeft of the radial tube. The proboscis is cruciform in cross section 
(see Fig. 16), and the lips are prominent. Green pigment spots are found in 
the ectoderm of the basal bulbs of the tentacles, and also upon the radial tubes 
close to their junction with the proboscis (Fig. 16). The entoderm of the 
radial tubes in the region of the gonads is tinged with green. The ectoderm 
of the bell margin is of a delicate rose color, and the proboscis and gonads are 
brown. 

This Medusa was common in Suva Harbor late in December. It is more 
closely allied to the species described by Murbach? from Wood’s Hole, Massa- 
chusetts, than it is to Gonionemus vertens, A. Agassiz, of the Gulf of Georgia, 
Washington. 


Aglaura prismatica, Maas. 


Plate 4, Fig. 13. 


Aglaura prismatica, Maas, O., 1897. Mem. Mus. Comp. Zod]. at Harvard Coll., 
Vol. XXIII. No. 1, p. 24, Pl. ITI. Figs. 4, 5. 

Lessonia radiata? Eydoux, F., et Souleyet, L., 1841-52, Voyage de la Bonite, 
Vol. II. p. 643, Zodphytes, Pl. II. Fig. 16. 


Generic Characters. Aglaura, Péron and Lesueur, 1809. Aglauride in which 
the 8 gonads are situated upon the peduncle of the proboscis, directly over the 
points of juncture of the 8 radial canals with the gastric portion of the pro- 
boscis. There are numerous tentacles, and 8 otocysts. 

Specific Characters. ‘The bell is about 3 mm. in height, and about as broad 
asitis high. The walls, although rigid, are exceedingly thin. The side walls 
of the bell are vertical, and the top is quite flat with, however, a slight apical 
projection. There are about 60 tentacles that are so fragile that they were 
broken off short in every specimen observed by us. There are 8 elub-shaped 
otocysts, situated midway between the 8 radial canals. Each otocyst contains 
a single otolith. The velum is very large and powerful, and it is chiefly by 
means of its rapid movements that the Medusa is enabled to dart. through the 
water. The 8 radial tubes are straight, and very narrow. The proboscis is 
flask-shaped, and provided with a well developed peduncle. There are 4 
prominent cruciform lips. The 8 sausage-shaped gonads: project outward 
from the sides of the peduncle at the point of juncture of the 8 radial tubes 
with the gastric portion of the proboscis. The gonads and entoderm of the 
proboscis are usually brownish red in color. Some specimens, however, are 
almost transparent. The Medusa was very common among the Fiji Islands. 

Maas, 1897, has figured a Medusa from the Gulf of Panama that we believe 
to be identical with our Fijian form. The differences between our figure and 


1 Murbach, L., 1895, Journ. Morphol., Boston, Vol. XT. p. 493. 
2 Agassiz, A., 1865, North American Acalephe, p. 128, Figs. 197-200. 


166° BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


those of Maas may readily be accounted for by the circumstance that his figures 
were drawn from preserved specimens that were probably distorted by con- 
traction. A very closely allied species is found at the Dry Tortugas Islands, 
Florida. 


Liriope hyalina, nov. sp. _ 
Plate 9, Fig. 32. _ 


Generic Characters. Liriope, Lesson, 1843. Geryonide with 4 gonads upon 
the 4 radial canals. The cireular canal is simple, and without blind, centripe- 
tal branches. There are 8 permanent tentacles; 4 of these are long, hollow, 
and radially situated, and 4 are short, solid, and interradial. Eight otocysts; 
4 radial, and 4 interradial. 

Specific Characters. 'The bell is about 1} times as broad as high, and the sides 
are straight and sloping. It is 6.5 mm. in diameter. There are 8 tentacles; 
4 of these are radial, and are about as long as the diameter of the bell. They 
are hollow, and are covered with rings of nematocysts. The other 4 tentacles 
are interradial and very short, and are carried curled sharply upward. 

There are 8 otocysts (4 radial and 4 interradiai), each containing a single 
spherical otolith. The velum is prominent. The radial canals are wide in the 
neighborhood of the circular vessel, where the gonads are found. In the upper 
portions of their length, however, near the proboscis, they are straight and 
slender. The proboscis projects for a considerable distance beyond the velar 
opening. The mouth opening is surrounded with nematocysts. This Medusa 
is extremely hyaline, excepting that the entoderm near the mouth of the pro- 
boscis is slightly rose colored. 

This form was found off Taviuni Island and in Suva Harbor. It is closely 
allied to Liriope scutigera, McCrady, of Charleston Harbor and the West 
Indies. 


4Hginella dissonema, Harcke. 


Eginella dissonema, Haeckel, E., 1879, Syst. der Medusen, p*340, Taf. XX. Fig. 16. 


This Medusa was found by us in the Fiji Islands. Haeckel describes it from 
the Canary Islands, and we have found it at the Dry Tortugas, Florida. Ina 
paper that will soon be published in this Bulletin, we hope to present a figure 
of it. 


?Cunina octonaria, McCrapy. 


Cunina octonaria, McCrady, J., 1857, Gymn. Charleston Harbor, p. 109, Pl. XIL, 
Figs. 4, 5. Also Proc. Elliot Soc., Vol. I. Pl. 1V.—VIL. 


Several specimens of a Cunina that is closely allied if not identical with 
Cunina octonaria of Charleston Harbor, South Carolina, were found by us in 
the Fiji Islands early in January, 1898. The Fijian form may be slightly less 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 167 


highly colored than McCrady’s species; the entoderm of the proboscis exhibit- 
ing no trace of the sage-green color that usually characterizes the Atlantic form. 
On this account we are in doubt as to whether the two forms are identical 
species. 


Oceania pacifica, nov. sp. 
Plate 5, Fig. 17. 


Generic Characters. Oceania, Péron and Lesueur, 1809. Eucopide with nu- 
merous otocysts scattered irregularly between the numerous tentacles. No 
marginal cirri. The 4 gonads are developed upon the 4 radial canals. There 
is no peduncle to the proboscis. 

Specific Characters. The bell is of moderate thickness, but is very flexible. 
It is hemispherical in shape, and is 6 mm. in diameter. There are 16 thin 
flexible tentacles of moderate length. The tentacle bulbs are large. There are 
two otocysts between each successive pair of tentacles, and each of these oto- 
cysts contains a single spherical otolyth. The velum is well developed. There 
are 4 straight, narrow, radial canals, in the middle regions of which the gonads 
are developed. The proboscis is short, and possesses 8 simple lips. The ento- 
derm of the tentacle bulbs, of the proboscis, and of the radial tubes in the 
region of the gonads is emerald green. 

Several specimens found at Suva and at Nukulau Island. 


Oceania ambigua, nov. sp. 
Plate 6, Figs. 18, 19. 


The bell is pyriform, and 4 mm. in diameter. The gelatinous substance is 
very thick. There are 16 short tentacles with large basal bulbs. There are 
either one or two otocysts between each successive pair of tentacles. Each 
otocyst contains a single spherical otolith. The velum is well developed. There 
are 4 straight, moderately wide radial canals. The gonads are situated upon 
these canals near to the proboscis. The proboscis is flask-shaped, and there 
are four simple lips. 

The entodermal axis of each tentacle is brown in color, and the ectoderm of 
the proboscis, gonads, and tentacles is green. 

Single specimen found at Suva, January 4, 1898. 


Clytia polynesie, nov. sp. 
Plate 6, Fig. 20. 


Generic Characters. Clytia, L. Agassiz, 1862. Eucopide with 16 tentacles 
alternating with 16 otocysts. Gonads upon the 4 radial canals. No peduncle 
to the proboscis. 

Specific Characters. The bell is thin and hemispherical in shape, and is 
5mm. in diameter. There are 16 short, sharply coiled, marginal tentacles, 


168 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


with large basal bulbs. Sixteen otocysts, each containing a single spherical - 
otolith, alternate with the 16 marginal tentacles. The velum is well devel- 
oped. There are 4 straight, narrow, radial canals, upon the lower region of 
which, near the circular canal, the gonads are developed. In the female the 
ova are very large and prominent. The proboscis is small and flask-shaped, 
and there are 4 curved lips. The entoderm of the proboscis, tentacle bulbs, 
and radial canals in the region of the gonads is green. 
Several specimens found in Suva Harbor early in January, 


Tiaropsis rosea, nov. sp. 


Plate 7, Figs. 21, 22. 


Generic Characters. Tiaropsis, L. Agassiz, 1849. Eucopide with 8 otocysts 
and 8 pigment spots (2 in each quadrant). There are numerous otoliths within 
each otocyst. The gonads are developed upon the 4 radial canals. There is 
no peduncle to the proboscis. . 

Specific Characters: Young Medusa. The hell in the young Medusa ob- 
served by us was ellipsoidal in shape, and 2.6 mm. in height. There were 4 
well developed marginal tentacles that were coiled in a close helix. The bulbs 
of these tentacles were large. In addition to the tentacles mentioned above, 
there were 4 small protuberances upon the bell margin that probably repre- 
sented the beginnings of other tentacles. ‘There were 8 marginal sense organs 
(Figs. 21, 22), 2 in each quadrant. These consisted (Fig. 22) of an entodermal 
pigment spot, and a number of otoliths contained in an open fold of the velum, 
A cross section (Fig. 23) of the sense organ of Tiaropsis diademata, L. Agassiz, 
will serve to illustrate their structure. In Figure 23 the entoderm is repre- 
sented in brown and the ectoderm in gray; the section is taken through the 
bell margin. It will be seen that the pigment spot ( pq.) is situated within the 
entoderm upon the inner side of the circular tube (cf.); and that the otoliths 
(ot.) are ectodermal and enclosed within an open fold of the velum (vel.). 

There were 4 straight broad, radial tubes. The proboscis was small, and 
there were 4 prominent, fimbriated lips. The gonads had not yet made their 
appearance. A number of immature specimens were found in Suva Harbor 
early in January. 

A species that is closely allied, if not identical, with this Medusa is found at 
the Dry Tortugas Islands, Florida. 


Mitrocoma mbengha, nov. sp. 
Plate 8, Figs. 24, 25. 


Generic Characters. Mitrocoma, Haeckel, 1864. Eucopidee with numerous 
open otocysts, and numerous tentacles and cirri. Gonads upon the 4 radial 
canals, No peduncle to the proboscis. 


: 
L 
A 
: 
4 


: 


Se ee 


a 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 169 


Specific Characters. The bell is slightly flatter than a hemisphere, and is 
9mm. in diameter. There are 16 short tentacles with large basal bulbs. In 
addition to these there are about 80 short cirri upon the bell margin. There 
are 32 otocysts (2 between each successive pair of tentacles). The otocysts 
each contain 5-9 otoliths. The velum is well developed. There are 4 straight, 
narrow radial canals, upon the lower regions of which the gonads are devel- 
oped. The proboscis is short and flask-shaped, and cruciform in cross section. 
There are 4 prominent, fimbriated lips. The entoderm of the tentacle bulbs 
and of the proboscis, and the ectoderm of the gonads, are dull yellow. The 
entoderm of the radial canals is grass-green, 

Suva Harbor, Fiji Islands, in January. 


Polycanna purpurostoma, nov. sp. 
Plate 8, Figs. 26-28. 


Generic Characters. Polycanna, Haeckel, 1879. quoride with numerous 
simple radial canals. Proboscis very wide; the mouth opening surrounded by 
numerous small lappets. Gonads upon the radial canals. 

Specific Characters. The bell is lens-shaped, and about three times as broad 
as itis high. It is about 30 mm. in diameter. The gelatinous substance of the 
bell is very thick, so that the cavity is shallow. There are 16 short tentacles 
with wide basal bulbs. In addition to these there are about 120 very small 
tentacles, or papille, upon the margin of the bell (see Fig. 28). There are 
about 100 otocysts, each one of which contains two small, spherical otoliths. 
The velum is prominent. There are about 100-120 straight, narrow radial 
tubes, upon the lower halves of which the gonads are developed. The pro- 
boscis is very wide and shallow, and the mouth opening large; there are 100- 
120 small lappets surrounding the mouth (M., Fig. 27). The entoderm of the 
basal bulbs of the tentacles is flesh colored. The gonads are slaty blue; and 
the proboscis, especially in young Medusz, is pink. In old individuals it is 
usually hyaline. 

Common among the Fiji Islands in December. 


Rhegmatodes floridanus, L. Acassiz. 


_ Rhegmatodes floridanus, Agassiz, L., 1862, Cont. Nat. Hist. U. S. A., Vol. IV. p. 361. 


A Medusa that we are unable to distinguish from Rhegmatodes floridanus 
of the Bahamas and Gulf of Mexico was met with occasionally in the Fiji 
Islands. 


Hirene kambara, nov. sp. 
Plate 8, Fig. 29. 


Generic Characters. Eirene, Eschscholtz, 1829. Eucopide with numerous 
otocysts and tentacles, and sometimes also marginal cirri. There is a distinct 


4 
170 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


peduncle to the proboscis. The gonads are developed upon a restricted portion 
of the 4 radial canals. 

Specific Characters. The bell is flat with sloping sides, and is 8 mm. in 
diameter. There are about 32 very small, slender tentacles, having well de- 
veloped basal bulbs. There are 64 otocysts, 2 between each successive pair of 
tentacles. Each otocySt contains a single spherical otolith. The velum is dis- 
tinct. The 4 radial canals are straight and narrow, and the gonads occupy 
their lower portions. There is a distinct peduncle. The proboscis is simple, 
and possesses 4 curved lips. The entoderm of the basal bulbs of the tentacles 
and the proboscis are turquoise in color. 

Single specimen found in Suva Harbor, December 29, 1897. This form 
differs from Eutima pyramidalis,! L. Agassiz, of the West Indies, in that the 
peduncle is smaller and the proboscis larger than in the Atlantic form. 


II SCYPHOMEDUSA. 
Tamoya, sp- 


A single specimen of Tamoya, in a very imperfect condition, was found by 
us in towing with an open net at 100 fathoms, three miles south of the entrance 
of Suva Harbor. 


Nausithoé punctata, var. pacifica, nov. var. 


Nausiihoé punctata, Kolliker, A., 1853, Zeit. fiir Wissen. Zool., Bd. IV. p. 823. 


This Medusa is extremely close to if not identical with Nausithoé punetata, 
Kolliker. It appears to differ from the latter, however, in that the brownish 
yellow spots upon the ectoderm of the ex-umbrella are not so prominent. As 
this difference appears to be constant, we consider the Fijian form to be a close 
variety of Nausithoé punctata. Nausithoé punctata is found in the Mediter- 
ranean, and we have taken it at the Dry Tortugas Islands, Florida. 


Linerges aquila, Harcket. 
Plate 10, Figs. 33, 34. 


Linerges aquila, Haeckel, E., 1879, Syst. der Medusen, p. 496. 


’ 

In the absence of a figure and an accurate description by Haeckel, we are 

far from certain that the species about to be described by us is identical with 
L. aquila of the east coast of Madagascar. 

Generic Characters. Linerges, Haeckel, 1880. Discomeduse with simple 

quadrangular proboscis without mouth arms, and with simple quadratic lips. 


1 We hope soon to publish a figure of Eutima pyramidalis in the Bulletin of the 
Museum. 


; 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 171 


There are 8 marginal sense organs, 8 tentacles, and 16 marginal lappets. There 
are 16 broad radial pouches and branched sac-shaped canals within the lap- 
pets. There is no ring canal. There are 4 horseshoe-shaped gonads, the con- 
vex proximal arches of which are divided into two adjacent wings by means of 
a median septum. There are 48-52 (in this species 52) wart-like, hollow pro- 
tuberances upon the floor of the sub-umbrella. 

Specific Characters: Adult Medusa. The bell is 13 mm. high, and 16 mm. 
in diameter. The side walls are straight and vertical, and the top flat. There 
are 16 marginal lappets that are about twice as wide as they are long. There 
are 8 small tentacles that are about 14 times as long as the lappets. Eight 
marginal sense organs alternate with the tentacles. The entoderm of these sense 
organs contains a spherical mass of otoliths (Fig. 34). The 4 gonads are crescent- 
shaped, the two horns of each crescent being separated by means of a median 
partition. There are 16 gastro-vascular pouches, and no marginal ring canal. 
Projecting inward from the floor of the sul-umbrella into the bell cavity there 
are 52 hollow wart-like protuberances. These are arranged in three rows. 
The most proximal row contains 4, the middle row 16, and the most distal 
row 32 of these protuberances. The proboscis is quadrangular in cross section, 
and there are 4 flanging lips. The general color of the Medusa is brown, 
There are 8 rows of dark brown pigment spots running longitudinally down 
the inner surface of the lips of the proboscis. Separated areas of brown ento- 
dermal cells are found in the distal portions of the 16 gastro-vascular pouches. 

Young Medusa. Ephyre of this Medusa were common among the Fiji 
Islands in November and December. They resemble the adult in general color, 
but the umbrella is very flat and disk-shaped. The youngest specimen observed 
by us was 2.5 mm. in diameter. 

We observed the ephyree of this Medusa off Taviuni, Ngamia, Wailangilala, 
and Vanua Mbalavu Islands, and in Suva Harbor. We also came: across a 
large swarm of the adults in the lagoon of Wailangilala Atoll on November 20. 

This Medusa differs from Linerges mercurius, Haeckel, of the West Indies in 
that there are 52 wart-like protuberances upon the sub-umbrella, instead of 48, 
as in the Atlantic species. Also the brown colored entodermal cells approach 
nearer to the stomach, and their color is perhaps slightly duller than in the 
West Indian form. 


Aurelia vitiana, nov. sp. 
Plate 10, Fig. 35. 


Generic Characters. Aurelia, Péron and Lesueur, 1809. Discomeduse with a 
simple central mouth, and 4 mouth arms or palps. The radial canals are nar- 
row and branched, and there is a ring canal. There are 8 marginal sense 
organs, and 8 broad, sometimes bipartite, marginal lappets, each of which 
bears on its dorsal side, some distance away from the umbrella margin, a row 
of numerous short tentacles, that alternate with as many dorsal lappets. 

Specific Characters. The bell is hemispherical and 80 mm. in diameter. The 
gelatinous substance is quite thick. There are 8 simple marginal lappets 

VOL. XXXII. — NO. 9. 2 


L772 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


that bear upon their dorsal surfaces, at a slight distance from the bell margin, 
a row of numerous short tentacles. The 8 marginal sense organs are large and 
deeply set within niches between the marginal lappets. Sixteen narrow chy- 
miferous tubes radiate outwards from the stomach cavity. Eight of these are 
straight and unbranched, and go to the middle of the marginal lappets. The 
8 others give off side branches that anastomose. They go to the marginal 
sense organs (see Fig. 35). The mouth arms, or palps, are short and narrow, 
and do not protrude beyond the bell margin. Their free edges are lined by a 
row of numerous short slender tentacles. The 4 gonads are horseshoe-shaped, 
and the subgenital pits are wide and open. The gonads, palps, and tentacle 
bulbs of the adult Medusa are of a delicate lilac. The bell is hyaline. Young 
Meduse lack the lilac color, and are quite transparent. 

This species was common upon the surface in Suva Harbor in the early 
morning hours in December, when the water was smooth and calm. A slight 
ripple seemed to be sufficient to cause them to sink out of sight. 


RHIZOSTOM A. 


Cephea dumokuroa,! nov. sp. 


Plates 11, 12, Figs. 36-39. 


Generic Characters. Cephea, Péron and Lesueur, 1809. Discomeduse without 
tentacles, and without a central mouth opening. There are 4 sub-genital cavi- 
ties, and ventral suction cusps upon the 8 mouth arms. The mouth arms give 
off short branches that are simple and not dichotomous. There are 8 ocular 
canals, and numerous other radial canals. There are 8 marginal sense organs. 

Specific Characters. The umbrella is disk-shaped, and the walls near the 
peripheri are vertical. It is about 300 mm. in diameter. <A large dome, coy- 
ered with thick conical protuberances, arises from the centre of the aboral sur- 
face of the umbrella. There are about 20 protuberances upon the dome. About 
8 of these are large, and the remainder are much smaller. There are 8 mar 
ginal sense organs that are deeply sunken within niches upon the bell margin 
(Fig. 39). The entodermal chore of these sense organs terminates in a mass 
-of small white (calcareous?) granules. There are about 9 very short marginal 
lappets in each octant of the umbrella. There are 8 short, thick, mouth arms, — 
the ventral surfaces vf which give rise to numerous short branches covered with 
suction mouths. Rows of very small tentacles surround these suction mouths. 
There are 4 sub-genital pits (gpt., Fig. 38). A general idea of the internal 
structure of the medusa is given by Figure 38. The stomach (S) is a wide 
cavity lying within the great central dome of the umbrella. It is completely 
separated from the sub-genital porticus (s. por.) by means of the double mem- 
branous folds of the genital organs (ov.). Thirty-two tubes (see Fig. 37) radi- 


1 Dumokuro is the native Fijian name for this species. 


7 =) 


<get.Ar* 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 173 


ate outward from the stomach cavity. Four of these tubes are wider than 
the remainder, and lead into 4 of the marginal sense organs. All of the radial 
vessels are connected one with another by means of a broad ring of anastomos- 
ing canals that occupies the peripheral zone of the umbrella. The 4 genital 
organs (ov., Fig. 38) are stretched upon 8 fleshy radii, and serve to separate 
the stomach cavity (S) from the cavity of the sub-genital porticus (s. por.). 
Hight chymiferous tubes spring from the cavity of the stomach, and enter the 
8 mouth arms, where they send off side branches to the suction mouths. These 
tubes also give off side branches that ramify and anastomose within the gelati- 
nous lower floor of the sub-genital porticus. None of these tubes, however, 
enter the cavity of the sub-genital porticus, that is thus separated entirely 
from the gastro-vascular system of the Medusa. The general color of the gelati- 
nous substance of the Medusa is blue. There are numerous deep blue streaks 
upon the apex of the central dome, and a deep blue band runs around the 
outer surface of the Medusa just above the mouth arms. This band is broad 
and biforked in the regions of the mouth arms. The chymiferous tubes in the 
mouth arms and the radial tubes of the umbrella are deep blue. The tenta- 
cles of the suctorial mouths and the anastomosing chymiferous vessels of the 
umbrella are coffee colored. 

We suddenly came upon a swarm of these Medusz off Vanua Mbalavu 
Island on November 25, and in all our subsequent voyaging through the Fiji 
group we never saw another specimen. The Medusze were accompanied by a 
number of small fish. 


Pseudorhiza Thocambaui,! nov. sp. 
Plate 13, Figs. 40-44. 


Generic Characters. Pseudorhiza, von Lendenfeld, 1884. Rhizostome with 
a single sub-genital cavity. There is a central mouth opening upon the lower 
side of the brachial disk. There are 8 mouth arms, the inner or ventral sides 
of which contain a deep groove. The mouth arms bifurcate, and there is a 
single long filament that arises from the place of bifurcation of each mouth arm, 
making in all 8 filaments. The canal system consists of 16 main radial canals 
and aring canal. Centrifugally from the ring canal there is an anastomosing 
network of canals, and centripetally there are between two adjacent main radial 
canals about 10 canals running from the ring canal inwards radially. 

Specific Characters. The bell is hemispherical and 32 mm. in diameter. 
There are 8 marginal sense organs, the sensory portion of which consists of a 
spherical chore of dark brown pigment granules, surrounded by a mass of small 
transparent otoliths (Fig. 41). There are 9 small marginal lappets between 
each successive pair of marginal sense organs. The brachial disk, upon which 


1 Named after Thocambau, king of Fiji. 


2 See Lendenfeld, R. von, 1884, Proc. Linn. Soc. New South Wales, Vol. IX 
Pp. 292. Also, 1887, Descrip. Catalogue Medusx, Australian Museum, p. 23. 


174 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


the mouth arms are borne, is attached to the lower floor of the umbrella by 
means of 4 pillars. There is a central mouth opening upon the lower floor of 
the brachial disk. Eight mouth arms arise from the brachial disk. Near their 
distal ends they bifurcate, and a single long filament arises from the place of 
bifurcation of each arm. Thus there are in all 8 of these filaments. These are 
each about 20 mm. in length, and their surface is covered with wart-like pro- 
tuberances. Numerous suctorial mouths are found upon the inner and lower 
sides of the mouth arms. They are surrounded by a great number of small 
tentacles, forming a row around each mouth opening. In addition to these 
small tentacles there are numerous club-shaped papille between the suctorial 
mouths. The surface of these papille is covered with clusters of nematocysts. 
The 4 gonads are V-shaped, the apex of the V being pointed inwards toward 
the centre of the disk. The canal system has been described under “ Generic 
Characters.” The color of the gelatinous substance of the umbrella is dull blue. 
The sub-umbrella, brachial disk, and mouth arms are dull green, and the 8 long 
filaments are deep blue. The 8 radial canals that run to the 8 marginal sense 
organs are green in color. The remaining radial canals, however, are almost 
colorless. There are a number of white spots upon the peripheral portions of 
the exumbrella, and the wart-like protuberances upon the 8 filaments are also 
white. 

The medusa was common in Suva Harbor in December. It swims with 
great rapidity by means of an incessant contraction and expansion of the um- 
brella. This movement is accomplished by the action of a powerful system of 
circular muscles in the sub-umbrella. 

Young Medusa (Figs. 42-44). A young ephyra of this species was captured 
in Suva Harbor on January 11, 1898. The bell was 5 mm. in diameter and 
qnite flat and disk-shaped. There were 8 marginal sense organs. The central 
mass of dark brown pigment granules of the sense organ was developed, but 
the peripheral shell of transparent granules had not yet made its appearance 
(compare Figs. 41 and 44). There were 24 marginal lappets, the 16 ocular 
lappets being about twice as long as the 8 intermediate lappets. There were 
16 radial pouches from the stomach. Eight of these went to the sense organs, 
and 8 to the intermediate lappets. The sub-genital porticus was already pres- 
ent, and the brachial disk was suspended from the floor of the sub-umbrella 
by means of 4 gelatinous pillars exactly as in the adult: The ephyra pos- 
sessed only a simple central mouth opening, having 4 cruciform lips. The 
margins of the lips were lined with a row of short, slender tentacles, with 
knob-like ends exactly like those that surround the suctorial mouths on the 
mouth arms of the adult Medusa. No trace of the genital organs could be — 
detected, but the gastric cirri were represented by 12 short filaments (3 in each 
quadrant). The color of the ephyra was very similar to that of the adult. 

Were it not for the sub-genital porticus and brachial disk, this little Rhizos- — 
toma would resemble, in all respects, the young of the Semostome. We have 
observed the ephyra of an allied genus, Stomolophus meleagris, L. Agassiz, 
that was in a slightly more advanced stage than the one here figured; and in 


ee a ae 


wes 


nl 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 175 


this individual the central mouth was still used for the capture of food. It 
seems probable that in those genera of Rhizostome that possess a single sub- 
genital space (the Monodenmia of Haeckel), the brachial disk has become 
separated from the floor of the sub-umbrella by the enlargement and final 
coalescence internally of the 4 sub-genital pits of the Semostome. 


Cassiopea ndrosia,! nov. sp. 
Plate 14, Figs. 45, 46. 


Generic Characters. Cassiopea, Péron and Lesueur, 1809. Discomedusz 
without tentacles and without central mouth. There are 8 pinnately or tri- 
chotomously branching mouth arms, the lower or ventral surface of which is 
occupied by numerous suction mouths and vesicles. There are 4 sub-genital 
cavities, and 4 gonads. There are 12 or more marginal sense organs, and 
numerous anastomosing radial canals. 

Specific Characters. The bell is flat and disk-shaped, and 50 mm. in diameter. 
The number of marginal sense organs appears to be variable. In the specimen 
here figured there were 22, but in another individual there were only 18. 
Whatever their number may be, they are situated at equal distances one from 
another. There are 4 small sub-genital ostia. There are 8 pinnately branch- 
ing mouth arms, each arm being about 30 mm. in length. Their ventral sur- 
face is occupied by a great number of suction mouths surrounded by small 
tentacles. In addition to these there are also a large number of leaf-shaped 
vesicles scattered among the suction mouths. These vesicles are more numer- 
ous near the centre than they are at the free ends of the arms. The umbrella 
possesses two powerful sets of radial muscle bands. Twenty-two of these (in 
specimens with 22 marginal sense organs) are situated in the floor of the sub- 
umbrella, and radiate outwards toward the marginal sense organs. An equal 
number are situated in the exumbrella, and alternate in position with the 
set in the sub-umbrella. The muscle bands of the floor of the sub-umbrella 
usually appear opaque and white in color, especially in states of contrac- 
tion. The muscles of the exumbrella, on the other hand, are deep blue- 
green. The general color of the umbrella is ashy brown. A large spearhead- 
shaped white spot is situated upon the radius of each sense organ at a little 
distance inward from the bell margin. Thus in a medusa with 22 marginal 


’ sense organs there are 22 of these large spots. The apex of each of these spots 


is directed outward toward the sense organ. In addition to these large spots 
there are usually 4 short white radial streaks between each pair of adjacent 
Sense organs. There are numerous white spots upon the inner portions of the 
sub-umbrella. The upper fleshy portions of the 8 mouth arms are white or 
slightly grayish. The tentacles surrounding the suction mouths are deep brown 
in color, and the leaf-shaped vesicles are olive-green. 


1 Ndrosi is the native Fijian name for this species. 


176 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


We found a specimen of this Medusa in Suva Harbor, November 14, 1897. 
And we also came upon a small swarm of them at Komo Island on November 
27, 1897. 

On January 3, 1898, we observed an individual of this species resting upon 
the muddy bottom of Suva Harbor. The aboral surface of the umbrella was 
pressed against the bottom, while the mouth arms and oral surface were 
uppermost. In this position it remained quiescent'for more than an hour, 
merely waving its mouth arms in a slow, sweeping manner. Indeed, its ap- 
pearance reminded one far more of an Actinian than of a Medusa. It is inter- 
esting to observe that the common Cassiopea frondosa of the West Indies, and 
also Cassiopea Mertensii, Brandt, of the Caroline Islands possess similar habits. 

The number of marginal sense organs in this species is certainly quite vari- 
able, and is greater than has as yet been observed in any other species of the 
genus Cassiopea. We prefer, however, on account of its close resemblance in 
all other respects, to place it in the genus Cassiopea. 


III. CTENOPHORAL. 


Eucharis grandiformis, nov. sp. 
Plate 15, Figs. 47, 48. 


The body of this Ctenophore is 135 mm. in length, and our figures represent 
the natural size of the animal. The lappets in this species are by no means so 
wide and voluminous‘as in the Mediterranean Eucharis multicornis,! Esch- 
scholtz. The whole outer surface of the body and lappets is covered with | 
numerous long papilla. The auricles are long, and are often carried coiled in 
a close helix (see Fig. 48). A pair of long unbranched tentacles arise from 
either side of the body near the region of the mouth. The ciliated plates are 
very numerous and close together, and are arranged in 8 rows. The oral sense 
organ is situated at the bottom of a deep cleft. The windings of the canal sys- 
tem through the lappets are far less complex than is the case in E. multicornis. 
The ciliated plates, gastric cavity, and chymiferous tubes are cinnamon-yellow 
in color. All other parts of the animal are hyaline. This Ctenophore is ex- 
tremely delicate in structure, the least touch being sufficient to tear the tissues 
of the animal. 

We found them in considerable numbers, floating near the surface, in Suva 
Harbor, early in the mornings of December when the water was perfectly 
calm, The least ripple caused them to sink to an unknown depth. 


1 Compare our figures with those of E. multicornis by Chun, C., 1880, Fauna 
und Flora des Golfe von Nezpel, I. Monographie, p. 296, Taf. V. Figs. 1-3. 


4 
: 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 177 


Beroé australis, nov. sp. 
Plate 16, Figs. 49, 50. 


The animal is 40 mm. in length, and the body is compressed laterally, one 
side being about three times as broad as the other. Our figure exhibits the 
broad side. The aboral otocyst is surrounded by a figure 8-shaped row of 
branched papillae. The long axis of this row lies in the plane of the broad 
side of the Ctenophore. There are 8 rows of ciliated plates that are bordered 
by masses of stellate pigment cells (see Fig. 50). Eight radial canals run be- 
neath the ciliated plates, and in addition to these there are two wide, straight 
lateral tubes (I., Fig. 49). All of these tubes communicate with the circular 
canal (c., Fig. 49) ; and are also put into further communication, one with an- 
other, by means of a simple network of connecting tubes (k., k., Fig. 49). The 
mouth opening is very wide and deep. The pigment cells of the ciliated plates, 
and of the papille surrounding the aboral sense organ, are crimson-lake in 
color. The gelatinous substance of the animal is quite transparent. 

Many specimens of this Ctenophore were found in Suva Harbor in December. 
The animal swims with remarkable rapidity by means of the movements of its 
combs of cilia. 


IV. SIPHONOPHORA. 


Physalia utriculus, Escuscuorrz. 


Physalia utriculus, Eschscholtz, F., 1829, Syst. der Acalephen, p. 163, Taf. XIV. 
Figs. 2, 3. 

Physalia australis, Lesson, R. P., 1830, Voy. de la Coquille, Zoophytes, p. 38, 
PV. Big. 1. 


Physalia utrleulus, Haeckel, E., 1888, Challenger Report, Zodlogy, Vol. XXVIII. 
p. 351. 


Several specimens of this Siphonophore were captured by us among the 
Fiji Islands. It is well represented by Lesson’s figure. 


Spheronectes Kéllikeri, Huxtey. 
Diplophysa Kollikeri, Harcket. 


S. Kollikeri, Plate 16, Figs. 51, 52. D. Killikeri, Plate 17%, Fig. 53. 


Spheronectes Kéllikeri, Huxley, T. H., 1859, Oceanic Hydrozoa, Ray Soc. Publica- 
tion, p. 50, Pl. III. Fig. 4. 

Spheronectes Kéllikeri, Haeckel, E., 1888, Challenger Report, Zodlogy, Vol. 
XXVIII. pp. 180, 361. 

Diplophysa Kéillikeri, Haeckel, E , 1888, Challenger Report, Zodlogy, Vol. XX VIL. 
pp. 107, 180, 39. 


178 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Generic Characters (Polygastric generation = Spberonectes). Polygastric 
Calyconecte with a single, rounded, edgeless, subspherical, swimming bell. 
There is a complete tubular hydreecium on the ventral side of the swimming 
bell, from the inner apex of which arises the long tubular hydrosoma. The 
groups of units are eudoxiform, and separated by free internodes. Each feed- 
ing polyp possesses a single covering scale. 

Generic Characters (Monogastric generation = Diplophysa). Monogastric 
Calyconecte, representing a single group of units, consisting in a feeding 
polyp with tentacle and covering scale, and a fertile gonophore that serves also 
as a swimming bell. The covering scale is hemispherical, or subspherical, and 
possesses a simple ovate or cylindrical canal (phyllocyst) within its ventral 
axis. 

Spheronectes Kollikert. —The swimming bell is about three quarters of a 
sphere in shape, and is about 10 mm. in diameter. The cavity of the bell is 
shallow; and there is a large and powerful velum, by means of the movements 
of which the animal is enabled to swim. The bell possesses a circular canal, 
and 4 narrow, somewhat crooked, radial canals (r, 7, 7,7, Fig. 51). These 
communicate, by means of the narrow duct (c), with the gastro-vascular cavity 
of the hydrosoma (h). There is a straight spindle-shaped vacuolated vesicle (/) 
buried within the gelatinous substance of the nectophore. The hydrosoma (/) 
arises from the inner end of a long, narrow invagination of the outer wall of 
the swimming bell (the hydrecium). The order of appearance of the various 
organules upon the hydrosoma is shown in Figure 52. The first to develop 
are the feeding polyps (p); then follow, in order, the tentacles (¢), the cover- 
ing scale (c.s.), and gonophore (g). The hydrosoma attains a length of about 
50 mm., and there are numerous groups of units (cormidia) separated hy free 
internodes. One of these groups of units that has very recently become sepa- 
rated from the hydrosoma, and is therefore in the Diplophysa stage, is repre- 
sented, highly magnified, in Plate 17, Figure 53. 

Diplophysa Kéllikeri (Plate 17, Fig. 53).— This is merely the free Mono- 
gastric or Eudoxia form of Spheronectes K6llikeri, and consists of a single 
group of units that has become separated from the hydrosoma of the latter 
animal, and leads an independent existence. The covering scale (c. s.) is thick 
and hemispherical in shape. It contains a simple ovate canal or phyllocyst 
(phe.). There is a single feeding polyp (p), a single tentacle (f), and a gono- 
phore (g). The tentacle gives rise to many small filamentous side branches, 
which terminate in nematocystic bulbs. The gonophore serves also as a swim- 
ming bell, and its manubrium will become much larger than is shown in 
Figure 53, and will contain the genital products. The tube ad. is the means 
by which the animal was once attached to the hydrosoma of S. Kéllikeri. This 
tube soon atrophies. The entoderm of the feeding polyps of the manubrium 
of the gonophore and of the nematocystic bulbs of the tentacles is rich yellow 
or orange. This animal, in the Spheronectes stage, was met with in various 
places among the Fiji Islands. Our drawings are derived from a specimen 
found upon the surface of Suva Harbor, December 12, 1897. 


J 


: 


i i a A i ee ee 


—_—e a re 


nascent 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 179 


This species is very closely related to Spheronectes gracilis, Claus, of the 
Mediterranean and Tropical Atlantic.1 We have taken S. gracilis at the Dry 
Tortugas Islands, Florida. 


Diphyopsis angustata, Harcket. 
Plate 17, Fig. 54. 


Diphyes angustata, Eschscholtz, F., 1829, Syst. der Acalephs, p. 136, Taf. 12, 
Fig. 6. 

Diphyopsis angustata, Haeckel, E., 1888, Challenger Report, Zodl., Vol. XXVIII. 
pp. 152, 363. 


Generic Characters. Diphyopsis, Haeckel, 1888. Diphyide with two angu- 
lar, slenderly pyramidal swimming bells of similar form and subequal size, 
one placed behind the other. The first swimming bell possesses a complete 
infundibular hydreecium on its ventral side. The groups of units upon the 
hydrosoma are Eudoxiform, and are separated by free internodes. Each feed- 
ing polyp possesses a covering scale. The covering scales are spathiform, with 
a deep ventral groove. 

Specific Characters. The specimens found by us conform to the definition of 
the genus Diphyopsis, with the notable exception that we observed no posterior 
swimming bell, such as is figured by Haeckel (1888, Plate XXXIII.) in Di- 
phyopsis compressa. It is possible that no such structure exists in Diphyopsis 
angustata, but knowing the ease with which swimming bells are broken off and 
lost, we hesitate to make such astatement. The anterior swimming bell (the only 
one observed) is 37 mm. in length. The bell cavity is long and spindle-shaped, 
and terminates in a long, narrow neck, in the end of which there are usually a 
number of vacuolated cells containing green pigment (cp., Fig. 54). There is 
a well developed velum, the sudden contractions of which cause the animal to 
shoot rapidly through the water. There is a circular vessel within the swim- 
ming bell, and also two long curving side tubes (7, r, Fig. 54). These com- 
municate by means of a long duct (c) with the gastro-vascular cavity of the 
hydrosoma. The cavity of the hydrecium is about 17 mm. in depth. There 
is a long spindle-shaped mass of vacuolated cells (f) extending from the inner 
apex of the hydrwcium into the gelatinous substance of the swimming bell. 
The hydrosoma also arises from the inner apex of the hydrecium. It often 
attains a length of 100 mm., and there are numerous groups of units (cor- 
midia) found upon it. These are separated one from another by free inter- 
nodes. The cormidia all arise from the ventral side of the hydrosoma. The 
first to appear are the feeding polyps. Then follow, in order, the tentacles and 
the covering scales. No gonads or swimming bells were seen. Each covering 
scale possesses a deep open groove along its ventral side. The tentacles give 
off simple lateral filaments that terminate in nematocystic bulbs. The ento- 


1 See Chun, C., 1892, Abhandl. d. Senckenb. naturf. Ges., Bd. XVIII. p. 84, 
Fig. 5. 


180 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


derm of the feeding polyps is rose colored, and the nematocystic bulbs of the 
tentacles are orange-yellow. 

This is the largest species of Diphyide known at the present time. 

Common among the Fiji Islands in December, 1897. 


Abyla quincunx, Cuvun. 


Abylopsis quincunr, Chun, C., 1888, Sitzungs Berichte Akad. Wissen. Berlin, 
p- 1160. 

Abyla (Abylopsis) quincunz, Chun, C., 1897, Verhandl. Deutsche Zool. Gesell., p. 71, 
Fig. 13. 


A large number of specimens of a polygastric Calyconectz that appears to be 
identical with Abyla quincunx, Chun, of the Tropical Atlantic, were found by 
us among the Fiji Islands. Huxley (1859, p. 58) mentions having found this 
form in the Indian and Pacific Oceans, and he describes it under the name of 
Abyla pentagona. Several specimens of the Eudoxia form of this species (see 
Aglaisma quincunx, Chun, 1888) were found by us while in the Fiji Islands. 
This Fiji form appears to be identical with one observed by us at the Dry 
Tortugas Islands, Florida. 


Agalma Pourtalesii, nov. sp. 


We obtained this beautifnl new Siphonophore near the mouth of Suva Har- 
bor, Viti Levu Island. We have also found a number of specimens that appear 
to be identical in all respects with the Fijian form, at the Dry Tortugas 
Islands, Florida. We hope soon to present a number of figures of this animal 
in a paper upon “ Meduse from the Tortugas” that is now in preparation, 
and will appear in the Bulletin. At present we will content ourselves by pre- 
senting a description of the species. 

Generic Characters. Agalma, Eschscholtz, 1825. Siphosome short and rigid, 
about as long as the nectosome. The whole siphosome is densely covered with 
thick prismatic bracts. The dactylozooide and feeding polyps are thickly 
scattered along the stem of the siphosome. The gonostyles spring from the 
internodes between the dactylozooide and feeding polyps. The tentilla are 
tricornuate, with a terminal ampulla and two paired horns. 

Specific Characters. The entire animal is about 25 mm. in length. The 
feeding polyps, tasterns, gonostyles, and tentacles all spring from the ventral 
side of the siphosome. ‘The float is of small size, and is balloon-shaped, and the 
pheumatopore is surrounded by radially arranged streaks of dark red pigment, 
The swimming bells are dovetailed alternately on either side of the nectosome, 
so that their velar openings are found on two diametrically opposite sides of the 
nectosome. The siphosome is densely covered upon all sides with thick pris- 
matic bracts. The feeding polyps are somewhat stouter in shape than the 
tasterns, but in other respects are quite similar to them in appearance. The 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 181 


tentacles arise from the bases of the tasterns and feeding polyps. Each tentacle 
gives off a number of lateral branches which terminate in a coiled nematocyst 
battery, an ampulla, and two paired horns. Both male and female gonostyles 
are found upon the same siphosome, and they arise from the side of the sipho- 
some between the tasterns and feeding polyps. The male gonostyles are long 
and slender, while the female are short and stout, and contain each one of them 
a considerable number of ove. Both male and female gonostyles are borne 
upon long, slender filaments that are highly contractile. The color of the ento- 
derm of the hydrosoma, swimming bells, feeding polyps, and tasterns is rose- 
red or pink. The nematocyst batteries upon the terminal portion of the 
tentacles are dark red. The gonads and braets are colorless. 


182 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


LIST OF SPECIES. 


Aydromeduse3 


* EX ginella dissonema, Haeckel . 
*Aglaura prismatica, Maas . 

Bougainvillea fulva, noy. sp. . 

Clytia polynesia, nov. sp. . . 
*Cunina octonaria, McCrady ? 

Cytzis vulgaris, nov. sp. 

Eirene kambara, nov. sp. . 
*Eutimeta levuka, nov. sp. 
*Gonionemus suvaensis, nov. sp. 
*Halitiaria formosa, Fewkes . 

Laodicea fijiana, nov. sp. . 

Laodicea marama, nov. sp. 

Liriope hyalina, nov. sp. 
*Mitrocoma mbengha, nov. sp. 

Oceania ambigua, nov. sp. 

Oceania pacifica, nov. sp. . 
*Pandea violacea, nov. sp. . 

Pennaria vitrea, nov. sp. 

Polycanna purpurostoma, nov. sp. . 
*Rhegmatodes floridanus, L. Agassiz . 

Staurodiscus nigricans, nov. sp. 
*Tiaropsis rosea, nov. sp. 


Scyphomeduse. 


Aurelia vitiana, nov. sp. 
Cassiopea ndrosia, nov. sp. 
Cephea dumokuroa, nov. sp. . 
*Linerges aquila, Haeckel ? A at 
*Nausithoé punctata, var. pacifica, nov. var. 
Pseudorhiza Thocambaui, nov. sp. 
SPATUUVAS ED. 615 «oe sis 0) 8, ot we ne ne eer 


Ctenophore. 


Beroé australis, nov. sp. 
Eucharis grandiformis, nov. sp. 


1i7 
176 


1 Medusmw whose names are preceded by an asterisk are represented both in the 
Fiji Islands and in the Atlantic Ocean by identical or very closely allied species. 


ah 
“i 
Ps | 


“ iy 


_ *Abyila quincunx, Chun 

_ *Agalma Pourtalesii, nov. sp. . 
_ *Agilaisma quincunx, Chun 
____Diphyopsis angustata, Haeckel 
_ *Diplophysa Killikeri, Haeckel 
_ Physalia utriculus, Eschscholtz 
PB, *Spheronectes Kollikeri, Huxley 


4 
iy 


t : AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 183 


184 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


LITERATURE CITED. 


Agassiz, A. 
1865. North American Acalephe. 234 pp., 360 Figs. 
Agassiz, A. 
1883. Report of Dredging by U.S. Coast Survey Steamer “Blake.” Mem. 
Mus. Comp. Zo6l. Harvard Coll., Vol. X. Part I., Report on Echini. 
126 pp., 32 Plates. 
Agassiz, A. 
1892. General Sketch of the Expedition of the “ Albatross,” from February 
to May, 1891. Bull. Mus. Comp. Zoél. Harvard Coll., Vol. XXIII. 
No. 1. pp. 1-90, 22 Plates. 
Agassiz, L. 
1849. Contributions to the Natural History of the Acalephe of North 
America. Mem. American Academy, Vol. IV. 2 Parts. pp. 221- 
374, 16 Plates. 
Asassiz, L. ; 
1862. Cont. Nat. Hist. U.S., Vol. IV. 380 pp., Plates XX.—XXXV. 
Brandt, J. F. 
1838. Ueber Schirmquallen. Mem. Acad. Impériale des Sci. de St. Péters- 
bourg, Sci. Naturelles, Ser. 6, Tom. LV. pp. 237-411, Taf. L—XXX1. 
Chun, C. 
1880. Die Ctenophoren des Golfes von Neapel. Fauna und Flora des Golfes 
von Neapel, Monographie I. 318 pp, 18 Tafeln. 
Chun, C. 
1888. Bericht iiber cine nach den Canarischen Inseln im Winter 1887-88 
ausgefiihrte Reise. Sitzungs Berichte Akad. Wissen. Berlin. pp. 
1141-1173. 
Chun, C. ¢ 
1892. Die Canarischen Siphonophoren. Abhandl. Senckenb. naturf. Gesell., 
Bd. XVIII. pp. 57-144, 5 Tafeln. 
Chun, C. 
1897. Ueber den Bau und Morpholog. Auffassung der Siphonophoren. 
Deutsche Zool. Gesell. Verhandl., pp. 48-111, Figs. in Text. 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 185 


Claus, C. 
1874. Die Gattung Monophyes und ihr Abkommling Diplophysa. Schrift. 


Zool. Inst. Wien, p. 25, Taf. IV. 


Eschscholtz, F. 
1825. Bericht iiber die Zoologische Ausbeute der Reise. Okens Isis. 


Eschscholtz, F. 
1829. System der Acalephen. 190 pp., 16 Tafeln. 


Eydoux, F., et Souleyet, L. 
1841-52. Voyages autour du monde sur la “ Bonite.” 2 Tom., 101 Pls. 
Paris. 
Fewkes, J. W. 
1882. Notes on Acalephs from the Tortugas. Bull. Mus. Comp. Zodl., 
Vol. IX. No. 7, pp. 251-289, 7 Plates. 


Goldfuss, A. G. 
1820. Handbuch der Zoologie. Nirnberg. Bd.I., II. 4 Tafeln. 


Haeckel, E. 
1879-80. Syst. der Medusen. 672 pp., 40 Tafeln. 
Haeckel, E. 
1888. Siphonophore. Challenger Report, Zodl., Vol. XXVIII. 380 pp., 
50 Plates. 
ol! RT. 


1898. The Geological History of the Isthmus of Panama, ete. Bull. Mus. 
Comp. Zodl., Geological Series, Vol. XXVIII. No. 5, pp. 151-285, 
19 Plates. 
Huzley, T. H. 
1859. Oceanic Hydrozoa. Ray Soc. 143 pp., 12 Plates. 
KOlliker, A. 
1853. Bericht iber einige im Herbste 1852 in Messina angestellte vergleich- 


end-anatomische Untersuchungen, II. Quallen. Zeit. fiir Wissen. 
Zool., Bd. LV. pp. 315-329. 
Lendenfeld, R. von. 
1884. Geographical Distribution of Australian Scyphomeduse. Proc. Linn. 
Soc. New South Wales, Vol. IX. pp. 421-433. 
Lendenfeld, R. von. 
1884. Scyphomeduse of the Southern Hemisphere. Proc. Linn. Soc. New 
South Wales, pp. 155-169, 259-306, Plates III. and IV. 
Lendenfeld, R. von. 
1887. Descriptive Catalogue of Scyphomeduse of Australian Seas. 2 Parts, 
pp. 1-32, 1-49, 1 Plate. 
Lesson, R. P. 
1830. Voyage de la Coquille. 135 pp., 1 vol. of Plates. Paris. 


186 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. | 


Lesson, R. P. 
1836. Mémoire sur la famille des Béroides. Annal. Sci. Nat., Tom. V. 
pp. 235-266. 
Lesson, R. P. 
1843. Histoire Naturelle des Zoophytes, Acalephes. Paris. 596 pp., 12 
Plates. 
Maas, O. 


1897. Reports on Exploration off West Coast of Mexico, etc., by Fish Com- 
mission Steamer “ Albatross,” during 1891. Mem. Mus. Comp. 
Zool., Vol. XXIII. No. 1. Die Medusen, pp. 1-92. 15 Plates. 


McCrady, J. 
1856. Descrip. Oceania (Turritopsis) nutricula, nov. sp., and the Embryo- 
logical History of a singular Medusan Larva, found in the Cavity 
of its Bell. Proc. Elliot Soc., Vol. I. pp. 55-90, Plates 4-7. 


McCrady, J. 
1857. Gymnophthalmata of Charleston Harbor. Proc. Elliot Soc., Vol. I. 
pp- 1038-221, Plates 8-12. 


Murbach, L. 
1895. Preliminary Note on the Life History of Gonionemus. Journ. Mor- 
phol., Vol. XI. pp. 493-496. 


Péron, F., et Lesueur, C. A. 
1807. Voyage de découvertes aux terres Australes. Mollusques et 
Zoophytes. 


Péron, F., et Lesueur,'C. A. S 
1809. Tableau caractéres génériques et specifiques de toutes les espéces de 
Méduses. Annal. Mus. Hist. Nat., Tom. XIV. pp. 325-366. 


Paris. 


Quoy, J. R. C., et Gaimard, P. 
1824. Voyage de l’Uranie et de la Physicienne. Zoologie. Paris. 


Quoy, J. R. C., et Gaimard, P. 
1833. Voyage de l’Astrolabe. Zoologie, Tom. IV. 


VanhOffen, E. 
1888. Untersuch. iiber Semaeostome und Rhizostome Medusen. Bibliotheca 
Zool., Bd. I. Heft 3, pp. 51. 6 Tafeln, 1 Karte. 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 


Fig. 


Le 


Fig. 2 


Sov [> co 


mls, 
. 19, 
. 20. 


VOL. XXXII. — NO. 9. S 


EXPLANATION OF THE PLATES. 


PLATE 1. 
Pennaria vitrea, nov. sp., female. R 
“ “ce “ce male. 
PLATE 2. 
Cytzis vulgaris, nov. sp. 
: ef Proboscis. 
c s One of the oral tentacles of the proboscis. 


Bougainvillea fulva, nov. sp. 


PLATE 3. 
Laodicea marama, nov. sp. 
¢ es Edge of bell. 


Laodicea fijiana, nov sp. 
o § Edge of bell. 


PLATE 4. 


Staurodiscus nigricans, nov. sp. . 
ss «s Edge of bell. 
Aglaura prismatica, Maas. 


PLATE 5. 


Gonionemus suvaensis, nov. sp. 

ss cs Edge of bell. 

cs s Aboral view of the proboscis. 
Oceania pacifica, nov. sp. 


PLATE 6. 


Oceania ambigua, nov. sp. 
3 ef Oral view of a quadrant of the bell. 
Clytia polynesia, nov. sp. 


187 


188 


Fig. 
Fig. 
Fig. 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


Fig. 
Fig. 
Fig. 


Fig. 
Fig. 
Fig. 


Fig. 
Fig. 


Fig. 


Fig. 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


21. 
22. 
25. 


59. 


40. 
41. 
42. 
43. 
44. 


BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


PEAT a7. 


Tiaropsis rosea, nov. sp. - 
af «« Marginal sense organ. 

Section through the marginal sense organ of Tiaropsis diademata, 
L. Agassiz: ent., entoderm; ect., ectoderm; ct., circular vessel, cut 
across; vel., velum; pg., pigment spot in the entoderm of the cir 
cular vessel; of., otolith. enclosed within an open pocket of the 
velum. 


PLATE 8. 


Mitrocoma mbengha, nov. sp. 

2 < Edge of bell. 
Polycanna purpurostoma, nov. sp. 

. = Oral view of a portion of the bell. J/., mouth. 
Edge of bell showing otocysts and tentacles. 


“ce “ 


Eirene kambara, nov. sp. 


PLATE 9. 


Eutimeta levuka, nov. sp. 
+ Edge of bell. 
Liriope hyalina, nov. sp. 


PLATE 10. 


Linerges aquila, Haeckel. 
Ky s¢ Marginal sense organ. 
Aurelia vitiana, nov. sp. 


PLATE OL: 
Cephea dumokuroa, nov. sp. Side view. 
& - Aboral view of the disk. 
PLATE 12. 


Cephea dumokuroa. Section to show the internal structure: gpt., sub- 
genital pit; m. s. 0., marginal sense organ; ov., genital organ; 7, one 
of the 8 thick gelatinous pillars that support the membranes of the 
genital organs; these radial pillars correspond in position with the 
8 mouth arms; S, stomach cavity; s. por., sub-genital porticus; rt., 
radial chymiferous vessel; t, chymiferous tube in the mouth arm. 

Cephea dumokuroa: Marginal sense organ. 


PLATE 13. 


Pseudorhiza Thocambaui, nov. sp. Adult Medusa. 
es Marginal sense organ of adult Medusa. 
“ 3 Side view of a young Ephyra. 
= " Oral view of a young Ephyra. 
ce ig Marginal sense organ of young Ephyra. 


AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 189 


Fig. 
Fig. 


Fig. 
Fig. 


Fig. 


Fig. 


Fig. 


Fig. 


Fig. 


Fig. 


46. 


47. 
48. 


61. 


62. 


53. 


54. 


PLATE 14. 


Cassiopea ndrosia, noy. sp. Side view. 
. $s Aboral view of disk. 


PLATE 15. 


Eucharis grandiformis, nov. sp. View of narrow side. 
es as View of broad side. (Figure uncolored.) 


PLATE 16. 


Beroé australis, nov. sp. View of broad side: /, lateral tube; k, side 
connecting tubes; c, circular tube. 

Beroé australis, nov. sp. View of ciliated plates and of stellate pigment 
cells. 

Spheronectes Kollikeri, Huxley: c, duct connecting radial vessels with 
the gastro-vascular cavity of the hydrosoma; c.s., covering scale; 
J, vacuolated vesicle; g, gonophore; i, hydrosoma; p, feeding polyp; 
r, 7,7, 7, radial vessels of the swimming bell; ¢, tentacle. 

Spheronectes Kollikeri, Huxley. Enlarged view of the hydrosoma. 
Lettering similar to Figure 51. 


PLATE 17. 


Diplophysa Kollikeri, Haeckel. The free Eudoxia form of Sphexronectes 
Kollikeri: ad., tube by means of which the group was once attached 
to the hydrosoma of S. Kollikeri; c. s., covering scale; g, swimming 
bell-gonophore; p, feeding polyp; phc., phyllocyst of the covering 
scale; ¢, tentacle. 

Diphyopsis angustata = Diphyes angustata, Eschscholtz: ec, duct con- 
necting the chymiferous vessels of the swimming bell with the gastro- 
vascular cavity of the hydrosoma; c.p., oleocyst; .f, vacuolated 
vesicle; h, hydrosoma; p, feeding polyp; v, v, ascending vessels of 
the swimming bell; ¢, tentacle. 


PLATE. 1, | 


' 
g 
<a 
= 
“oe 
na 
= 
= 
le 


Le) Be ee ee ~ a ee 


- 


FI AGALEPHS.  -~PLatE 2. 


i 


B Meisel th Baste 


Prate. 3. 


\ VAS Wavananeen ssa 


yc 


QS 


— 


ee 


é ii 
is 


TAA RPTTERTIN TO 
6 


pO 


ne ama 


wr 


y 


B Meise] Wth, Sesto 


B Meisel lth Baste 


PLATE 4, 


\ \ 
e Ht . SAM iS 
\ 


sah 3; 


we 
—— 
—<, 
tt _, < 


— 
~~ 


—. 
a 
$e 
OL Se 
i 


st 
os 
a a 


> 
—_——ow 
Y 


ae 
sr 


LL. 


‘Fit AGALEPHS. 


PPHDY 
“Wsog”ypi [OSTA Y 


“/ 


te 


PLATE. 6. 


B Meisel Wh fede 


¢ 


Fit ACALEPHS. PrAtTE: 7: 


B Meisel With deste 


PLATE 8. 


; 7 < 
A \ 


B Meisel ih Bestve 


B Meisel lith Beste 


Pirate 10. 


Fil ACALEPHS. 


B Meisel ith Bete 


‘ B Meisel hth Sect 


ae ae 


‘SHdATVOY IPI 


—- — 


_ Fit ACALEPHS. . PLATE. 13. 


Ta 


B Meise! bth esis 


PLATE. 14. 


Fiut ACALEPHS. 


Paes 


Pirate 16. 


IO 


B Meisel ith Sect 


Bulletin of the Museum of Comparative Zoology 
AT HARVARD COLLEGE. 
Vou. XXXII. No. 10. 


REPORTS ON THE RESULTS OF DREDGING, UNDER THE SUPERVISION 
OF ALEXANDER AGASSIZ, IN THE GULF OF MEXICO AND THE 
CARIBBEAN SEA, AND ON THE EAST COAST OF THE UNITED 
STATES, 1877 TO 1880, BY THE U. S. COAST SURVEY STEAMER 
“BLAKE,” LIEUT.-COMMANDER C. D. SIGSBEE, U.S.N., AND COM- 
MANDER J. R. BARTLETT, U.S. N., COMMANDING. 


[Published by Permission of CARLILE P. PATTERSON and HENRY S. PRITCHETT, Superin- 
tendents U. S. Coast and Geodetic Survey.] 


XXXVIII. 


ETUDE MONOGRAPHIQUE 
DES 


PLEUROTOMAIRES ACTUELS. 


Par E. L. Bouvier et H. Fiscuer. 


: AVEC QUATRE PLANCHEs. 


CAMBRIDGE, MASS., U.S. A. : 


PRINTED FOR THE MUSEUM. 
Sept, 1899. 


No. 10. — Reports on the Results of Dredging, under the Supervision 
of Alexander Agassiz, in the Gulf of Mexico and the Caribbean 
Sea, and on the East Coast of the United States, 1877 to 1880, 
by the U. S. Coast Survey Steamer “ Blake,” Lieut.-Commander 
C. D. Sigsbee, U. S. N., and Commander J. h. Bartlett, U.S. N., 


Commanding. 


[Published by Permission of CARLILE P. PATTERSON and Henry S. Prit- 
CHET, Superintendents of U. S. Coast and Geodetic Survey. ] 


XXXVIII. 


Etude Monographique des Pleurotomaires actuels. Par E. L. Bouvier et 
H. FiscHer. 


Le mémoire que nous présentons aux zoologistes est une sorte de 
monographie oi nous nous sommes efforcés de réunir les faits les plus 
importants relatifs 4 l’histoire des Pleurotomaires actuels. Il se com- 
pose de deux parties bien distinctes, lune purement historique, ot nous 
avons condensé les observations de nos prédécesseurs et les renseigne- 
ments que nous avons pu recueillir sur les exemplaires connus de ce 
curieux genre; l’autre anatomique et essentiellement consacrée 4 nos 
recherches personnelles. Si la premiere partie est destinée 4 rendre des 
services aux hommes de science et a faciliter leurs recherches, la seconde, 
croyons-nous, jettera quelque lumiére sur les animaux qui nous occupent 
et sur l’évolution des Gastéropodes. Les Pleurotomaires, en effet, sont 
les plus anciens de tous les Mollusques aujourd’hui connus; on les 
rencontie dans les couches fossiliféres les plus primitives, et l’on était en 
droit de supposer, méme avant de connaitre leur animal, qu’ils servi- 
raient quelque jour a rattacher les Gastéropodes archaiques aux formes 
qui leur ont donné naissance. Ces prévisions furent confirmées en 
partie quand, 4 Ja suite des heureux dragages entrepris par le “‘ Hassler” 
et le “Blake,” M. Dall put examiner des animaux de ce genre et se 
convaincre qwils avaient deux branchies bipectinées symétriques, deux 
orifices rénaux et un anus situé sur la ligne médiane dorsale. II restait 
toutefois 4 pousser plus loin les recherches et d faire, pour les organes 


vitaux, ce que M. Dall avait réalisé pour la morphologie. 
VOL. xxx11. — No. 10. 1 


194 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Ce desideratum, formulé par beaucoup de zoologistes, sera satisfait, 
dans une certaine mesure, par la publication du préseht mémoire. Grace 
a la libéralité éclairée et 4 la générosité scientifique de M. Alexandre 
Agassiz, nous avons eu la fortune, que beaucoup nous envieront, sans 
doute, de posséder un des animaux du Pleurotomaria Quoyana recueillis 
par le “ Blake.” C’est le premier animal du genre dont on ait fait 
Vanatomie ; nous avons eu toute liberté pour l’étudier; il nous a été 
livré généreusement, sans condition aucune, et c’est pourquoi nous avons 
réussi, bien qu'il fat incomplet, 4 en tirer un parti qu’on ne trouvera pas 
sans intérét, nous l’espérons, du moins. 

Quelle que soit, du reste, la valeur des observations qui vont suivre, 
nous en rapportons tout le mérite 4 l’éminent directeur des campagnes 
du “ Blake,” a M. Alexandre Agassiz. A l’auteur de tant de belles dé- 
couvertes, au naturaliste qui a su retrouver dans les océans les restes de 
faunes qu’on croyait éteintes, nous sommes heureux de dédier ce mémoire, 
en lui présentant l’hommage de notre respectueuse reconnaissance.? 


PREMIERE PARTIE. 
Etat Actuel de nos Connaissances sur les Pleurotomaires. 


PLEUROTOMARIA (DEFRANCE), SOWERBY, 1821. 


Le terme générique Pleurotomaria n’est pas apparu subitement dans 
la nomenclature zoologique et il semble avoir été assez généralement 
employé avant d’étre décrit et publié. C’est en juin 1821,* que nous 
trouvons la premiere indication du nouveau genre, dans les ‘‘ Tableaux 
systématiques”’ de Férussac. II s’agit de la simple citation suivante : 

“Genre VI, PLeurotomarre, Pleurotomaria? Defrance.” Le point 
d’interrogation placé aprés Plewrotomaria se rapporte probablement au 
nom latinisé Pleurotomaria (qui pouvait avoir différentes terminaisons), 
traduction du nom Pleurotomaire de Defrance; il est peu probable, en 
effet, que le baron de Férussac ait eu quelques doutes en attribuant la 
paternité du genre a Defrance, car les auteurs suivants n’ont pas la 


1 Nous remercions également M. Agassiz d’avoir bien voulu nous permettre de 
publier en France ce travail qui fait partie des “ Reports on the Results of Dredg- 
ng, under the Supervision of Alexander Agassiz, ... by the U. S. Coast Survey 
Steamer, ‘ Blake.’ ” 

2 Cette date de publication nous est fournie par Dall (81, 77). D’autres auteurs 
indiquent soit 1821, soit 1822. 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 195 


x 


moindre hésitation 4 ce sujet. L’ouvrage en question fait partie de 
“)Histoire naturelle générale et particuliére des Mollusques terrestres 
et fluviatiles,”’ etc., du pere Férussac dont la publication a commencé 
en 1819. 

En décembre, 1821, James Sowerby (’21) dit quelques mots du genre 
Pleurotomaria sans en nommer l’auteur; ces quelques mots suffisent 
d’ailleurs pour le caractériser : 

“ Trochus Gibsi. . . . the upper part (of the shell) is smooth, except 
the concentric band, upon which are semicircular striz, indicating a 
sinus in the outer lip. ... 

“This and several other shells, hitherto called Trochi, with the band 
around the spire, may more properly belong to the genus Plewrotomaria, 
which I may be induced at some future period to adopt.” 

Cette description, d’aprés M. le professeur Dall,’ confere la priorité du 
genre a James Sowerby. 

Il est certain que la citation faite par le baron de Férussac ne peut 
pas €tre considéré comme suflisante pour établir le genre; au contraire, 
la description de James Sowerby met en évidence les caractéres essentiels 
du Pleurotomaria ; mais il est beaucoup plus douteux que James Sowerby 
ait entendu décrire explicitement ce genre comme résultant de ses re- 
cherches personnelles. Dans le passage que nous venons de citer, l’auteur 
parle, en effet, du Pleurotomaria comme d’un genre bien connu, familier 
& tous les zoologistes de cette époque et dont il est superfiu, par consé- 
quent, de nommer l’auteur. II ajoute qu’il pourra étre conduit ulté- 
rieurement a l’adopter; cette derniére expression suffirait presque A 
prouver que le paléontologiste anglais n’est pas l’auteur du genre en 
question. - 

Deux ans plus tard (sept. 1823),? Defrance publie (23) les figures de 
deux espéces, avec la légende suivante : 

2. Pleurotomaire ornée (Defr.). 
3. Pleurotomaire tuberculeuse (Defr.). 

En 1824, Defrance ne fait que citer le genre Pleurotomaire dans son 
“Tableau des corps organisés fossiles”’ ('24) ; enfin, en 1826, il donne 
la description du genre et cite cinq espéces : 

Pleurotomaria tuberculosa Defr., Pl. anglica Defr., (Trochus anglicus 
et similis Sow.) ; Pl. granulata Defr. (Trochus granulatus Sow.); Pl. 


1 Dall (’81 et ’91, 396). 

2 Voir, pour la date de publication des planches du vingt-sixitme cahier de 
“YPAtlas du Dictionnaire des sciences naturelles, la bibliographie de la France,” ou 
“Journal général de l’imprimerie et de la librairie,” Pillet ainé, Paris, 1823. 


196 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


ornata Defr. (Trochus ornatus Sow.); Pl. elongata Defr. (Antrochus 
elongatus ? Sow.). 

J. Sowerby (’31), dans un fascicule de son ‘Genera of Recent and 
Fossil Shells,” publié fin 1830 ou commencement de 1831,1 donne la 
diagnose du genre et figure deux especes (Pleurotomaria reticulata et 
Pl. elongata). Il ajoute: “On the genera distinguished by a more or 
less deep fissure or notch in the upper part of the outer lip, the Pleuro- 
tomaria of Defrance has no canal...” Ce passage de Sowerby Ilui- 
méme reconnait formellement la priorité 4 Defrance. Une deuxiéme 
fois, en 1844, Sowerby (’44), cite Defrance comme l’auteur du genre. 

C’est 4 l'aide des documents précédents que nous devons attribuer la 
priorité soit a Defrance, soit & Sowerby. I] nous semble que, dans le 
cas actuel, l’application stricte des lois de priorité est impossible ; la 
citation des “ Tableaux systématiques” doit étre écartée ; la description 
de Trochus Gibsi par J. Sowerby (’21), avec les remarques qui l’accom- 
pagnent renferment, au contraire, une bonne définition ; mais il y aurait 
encore li matiére 4 discussion, car le nouveau terme Pleurotomaria n’est 
pas proposé a titre définitif par l’auteur, qui se contente d’annoncer qu’il 
- ladoptera peut-étre plus tard. 

La premiére définition réellement complete et indiscutable du nouveau 
genre est celle qu’a donnée Defrance en 1826, précédée par la planche 
publiée en 1823. II faut done choisir entre les deux notations: Pleuro- 
tomaria J. Sowerby 1821 et.Pleurotomaria Defrance 1826 : la premiere a 
Vavantage de la priorité, mais sa valeur n’étant pas absolument démontrée, 
la question nous parait insoluble, comme nous le disions plus haut. 

Il faut done renoncer & faire ici l’application étroite des regles de la 
nomenclature. Il nous semble que l’idée premiére du genre nouveau re- 
vient 4 Defrance, qui l’avait reconnu depuis un certain temps déja, sans 
le publier ; Sowerby eut naturellement connaissance de la nouvelle coupe 
générique grace aux rapports qu’il entretenait avec Defrance ; on lit, en 
effet, dans la préface des ‘“‘Tableaux des corps organisés fossiles,” ? que 
ce dernier avait obtenu de J. Sowerby la communication d’un certain 
nombre de fossiles; on comprend trés bien, dans ces conditions, que 
Sowerby, en 1821, ait parlé du nouveau genre, sans d’ailleurs se pro- 
noncer complétement sur sa valeur, et qu’il ne lait adopté deéfinitive- 


1 Voir, pour la date de publication du trente deuxitme cahier de cet ouvrage: 
D. Sherborn, “On the Dates of Sowerby’s Genera of Recent and Fossil Shells” 
(Annals and Magazine of Natural History, Vol. XIII, 1894, p. 8370; R. B. Newton, 
Syst. List Edwards Collection (Catal. Brit. Mus., 1891, p. 821). 

2 Defrance (24, x). 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 197 


ment, en 1831, qu’apres la description de Defrance, et en lui rendaunt 
entiére justice. Il nous semble donc tout indiqué de nous ranger a 
Yopinion de Sowerby lui-méme et de considérer Defrance comme le véri- 
table auteur du genre; nous croyons avoir ajouté quelques arguments 
4 Pappui de cette maniére de voir, que nous partageons avec H. Wood- 
ward (’85). En résumé, nous admettrons comme références originales, 
A la fois la citation de Férussac (’21), prouvant que le genre était adopté 
par Defrance en 1821, et le passage du ‘“ Mineral Conchology ” de J. 
Sowerby (’21), évidemment inspiré par Defrance, et qui met en évidence 
les caractéres du nouveau genre. Nous adopterons done la notation 
suivante : ; 

Pleurotomaria Defrance (Sowerby) [’21, x]. 

En terminant ce chapitre, nous adressons nos vifs remerciements a 
MM. Deniker, de Paris, Sherborn et Gude, de Londres, qui nous ont 
fourni de précieux renseignements sur les dates de publication des pre- 
miers ouvrages ot il est question du genre Pleurotomaria. 

Le genre Pleurotomaria est largement représenté dans les terrains 
sédimentaires. En 1885, Etheridge et H. Woodward (’85) ont fait le 
recensement des espéces fossiles et en ont signalé 1156: ce nombre a été 
un peu augmenté depuis. 

La premiére espéce connue se rencontre dans le cambrien inférieur 
(zone & Olenellus) des Etats-Unis, c’est-a-dire dans les plus anciens s¢di- 
ments fossiliféres : c’est le Plewrotomaria (Raphistoma) Attleborensis Shaler 
et Foerste (’88), décrit d’aprés un fragment trouvé a North Attleborough, 
Mass. Les Pleurotomaires sont done contemporains des plus anciens 
Trilobites et des plus anciens Brachiopodes, qui ont été longtemps con- 
sidérés comme les plus vieux animaux. 

A VPépoque silurienne, les espéces sont déji trés nombreuses, surtout 
en Amérique ; leur nombre augmente encore au carboniftre et atteint 
son maximum pendant la période jurassique (367 espéces d’aprés Wood- 
ward). La diminution commence 4 se faire sentir au crétacé. Les sédi- 
ments tertiaires ne renferment que tres peu d’especes, et, pendant 
longtemps, on n’en connaissait que quelques unes dans Il’éocéne ; |’ab- 
sence compléte du genre a partir du miocéne avait méme fait supposer 
que les Pleurotomaires étaient complétement et définitivement ¢teints : 
ceci explique le vif intérét qu’a excité la découverte de la premiére espece 
vivante.* Cette lacune est maintenant en partie comblée. E. Vincent (°90) 


1 Morch avait cru retrouver A |’état vivant un autre genre fort intéressant. Voir 
la description de Murchisonia (Murchisonella) spectrum, de Vile Saint-Thomas (Malak. 
Blatter, 1885, T. XXII, p. 184); mais cette forme est actuellement placce par les 
auteurs pres des Turbonilla. 


198 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


signale, en 1896, treize espéces éocénes ; H. Crosse (82, 6) en indique 
deux dans la miocéne: Pleurotomaria Sismondai Goldfuss du miocene de 
Biinde et Pl. tertiaria MacCoy d’Australie. Deux autres especes ont 
été trouvées dans les tufs madréporiques quartenaires de la Guateloupe : 
Pleurotomaria Fischeri Mayer ms et Pl. Duchassaingi Schramm (’69) ; 
malheureusement elles n’ont pas été clairement définies. Nous ajoute- 
rons 2 cette liste une forme des terrains tertiaires récents d’Italie: Pleu- 
rotomaria gigas Borson et une espéce miocéne de Vile Santa-Maria 
(Agores) : Pl. atlantica Cotta.* 


CoMPARAISON DES EsPECES VIVANTES AVEC LES EspkcEs FOssILEs. 


Les espéces vivantes sont rangées dans les deux sections Entemnotro- 
chus P. Fischer et Perotrochus P. Fischer (85). Les Entemnotrochus 
(Pleurotomaria Adansoniana et Pl. Rumphit), caractérisés par la position 
élevée (supra- médiane) du sinus et par leur ombilic, se relient a une 
série de formes erétacées rangées dans la section Leptomaria. Une 
espece éocene le (Leptomaria) landinensis Vincent (’96), du landénien 
inférieur belge, présente aussi quelques rapports avec le Pl. Adansonzana. 
En outre, il existe dans le tertiaire de l’Italie septentrionale un véritable 
Entemnotrochus, le Pleurotomaria gigas Borson, Dans un travail récent 
('97), Sacco signale, en effet, les rapports étroits qui unissent cette espece 
au Pl. Rumphii ; dautre part, elle a aussi des affinités avec Pespéce mio- 
céne de Biinde, Pl. Sismondai Goldfuss. Sacco n’est méme pas éloigné 
@admettre que Pleurotomaria Rumphii provienne directement de Pi. 
gigas et celui-ci de Pl. Sismondai. D’aprés Vauteur, le Pleurotomaria 
atlantica Cotta présente également les plus grands rapports avec les 
Entemnotrochus, et est peut-étre méme identique 4 Pl. gigas. 

Les Perotrochus (Pleurotomaria Quoyana et Pl. Beyrichir), caractérisés 
par la situation inframédiane du sinus et par l’absence d’ombilic se relient 
& quelques formes jurassiques * qui semblent appartenir & cette section. 

Les deux sections actuellement vivantes du genre Plewrstomaria sont 
done représentées & l’état fossile, mais il n’est pas encore possible de 
préciser la filiation de chaque espéce. 


Espkces VIVANTES DE PLEUROTOMARIA. 


Les esptces vivantes du genre sont actuellement au nombre de quatre : 
le lecteur trouvera plus loin, dans la liste des spécimens, Vindication des 
descriptions et des figures originales, 4 propos de chaque type; nous 


1 Sacco (’97) et Borson (’21). 2 Pp. Fischer (’85, 850). 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 199 


~ nous contenterons donc ici de donner leurs caractéres différentiels et 


leur habitat. 

Ces espéces sont, par ordre de découverte : 

Pleurotomaria Quoyana P. Fischer et Bernardi, 1856. 

Pleurotomaria Adansoniana Crosse et P. Fischer, 1861. 

Pleurotomaria Beyrichw Hilgendorf, 1877. 

Pleurotomaria Rumphii Schepman, 1879. 

Ces quatre espéces doivent étre réparties en deux sections, qui ont 
déja été définies par H. Crosse en 1882 (’82, 8), mais sans étre nommées. 
En 1885, P. Fischer (’85) a proposé pour ces deux sections les noms 
Entemnotrochus et Perotrochus. 

Nous résumons en un tableau les caractéres differentiels les plus 
évidents qui permettent de reconnaitre ces espéces, d’ailleurs trés 


distinctes : 

Dernier tour fortement strié longitudinalement 
et portant des granulations au voisinage de 
la suture. Coloration: flammules rouges sur 
fond rosé. 

Espéce de trés grande taille, habitant les An- 


SEecTION 1: Entemnotrochus. tilles. 


: : 3 Pleur aria Adansoniana, Cr. et Fisch. 
Sinus situé au-dessus du mi- ae d ’ t Fisch 


lieu du dernier tour; un 
ombilic.+ 


Sculpture trés atténuée sur le dernier tour ; 
entaille beaucoup plus étroite que dans 
Pespéce précédente. Coloration : flammules 

| passant du rouge orangé au rouge carmin et 
au violet clair, sur fond jaune blanchatre. 

Espéce de taille gigantesque, provenant des 
Moluques. Pleurotomaria Rumphii, Schep. 


spiraux rendus subnoduleux par leur croise- 
ment avec des stries longitudinales. Colora- 
tion: flammules rouge vif sur fond jaune 
clair. 
Section II: Perotrochus. Espéce de grande taille, habitant les mers du 
Sinus situé au-dessous du}. Japon. . . Pleurotomaria Beyrichii, Hilg. 
millieu du dernier tour ; 
pas d’ombilic. 


| Sculpture tres accentuée formée de cordons 


Sculpture beaucoup plus fine et plus réguliére 
que dans l’espéce précédente. Coloration : 
taches ou flammules obscures rouge brunitre 
sur fond rosé. 

Espéce de taille médiocre, habitant les Antilles. 

Pleurotomaria Quoyana, Fisch et Bern. 


1 Le sinus fournit un excellent caracttre pour ces deux sections; il est tres long 
chez les Entemnotrochus, beaucoup plus court chez les Perotrochus. 


200 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Recensement des Hxemplaires Connus de Pleurotomaires 
Actuels. 


Les Pleurotomaires actuels figurent encore aujourd’hui parmi les 
grandes raretés conchyliologiques; le nombre des exemplaires trouvés 
jusqu’a présent déposés soit dans des musées, soit dans des collections 
particulieres, dépasse A peine une vingtaine. I] est certain que ce nom- 
bre s’accroitra fortement par la suite, lorsque les conditions d’existence 
de ces animaux seront mieux connues; mais en attendant ce moment, 
peut-étre encore lointain, il nous a semblé utile de recueillir tous les 
renseignements possibles sur ces premiers spécimens et d’indiquer ceux 
qui ont été figurés. Nos recherches nous ont été grandement facilitées 
par MM. Crosse et Dautzenberg, de Paris; MM. les professeurs Dall, de 
Washington ; Déderlein, de Strasbourg; E. von Martens, de Berlin ; 
Smith et Woodward, de Londres; ainsi que par MM. Damon, de Wey- 
mouth ; Fulton et Sowerby, de Londres ; Schneider, de Bale, auxquels 
nous adressons nos bien vifs remerciements. 

Il existe au moins vingt et un spécimens distincts dont voici ’énumé- 
ration. 

1. Pleurotomaria Quoyana (Tyre). — C’est en 1855 que le premier 
exemplaire de Plewrotomaria actuel a été recueilli par le commandant 
Beau ‘‘sur une nasse mouillée 4 une grande profondeur, 4 plusieurs 
milles du rivage de Marié-Galante, entre cette ile et la Dominique.” } 
La coquille était intacte ; animal et lopercule manquaient. P. Fischer 
et Bernardi (’56) ont décrit et figuré ce premier spécimen et signalé 
Yimportance exceptionnelle de sa découverte. Cette belle coquille fit 
ensuite partie de la collection de M. Rolland du Roquan; 4 la mort de ce 
dernier, elle fut vendue successivement & M. Moitessier, 4 M. R. Damon, 
et enfin, en 1872, pour le prix relativement faible de 25 guinées & 
Mrs. de Burgh? dont la collection, aprés sa mort, est échue & Miss de 
Burgh, qui en est actuellement propriétaire. 

2. Pleurotomaria Adansoniana (Typr). — La seconde espeéce connue 
a été décrite et figurée par H. Crosse et P. Fischer (61)), d’aprés un 
exemplaire incomplet qui gisait ignoré dans la collection du docteur 
Commarmand. Cette eoquille a été achetée, en 1858, par M. H. Crosse, 
qui la posséde encore actuellement.® 


1 Hf. Crosse et P. Fischer (’61), p. 155. 

2 H. Crosse et P. Fischer (’61, 155); H. Crosse (’82, 16); Cooker (’95, 122). 

3 Ce spécimen vient d’étre légué Al’un de nous par le savant et regretté Directeur 
du “ Journal de Conchyliologie,” décédé pendant l’impression de ce mémoire. 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 201 


3. Pleurotomaria Quoyana. —Cet exemplaire est le premier qu’on 
ait recueilli avec animal; il a été capturé par L. Agassiz, en décembre 
1871, lors de l’expédition du ‘“ Hassler,” pres des Barbades, par 100 
brasses environ de profondenr. Quelques détails concernant son organi- 
sation ont été publiés, en 1872, par L. Agassiz (72) et reproduits, peu 
de temps apres, dans une note de E. von Martens (’72).4 L’opercule 
manquait. Ce spécimen est déposé dans les collections du Museum of 
Comparative Zodlogy, 4 Cambridge (U. 8.). 

4. Pleurotomaria Beyrichii (Type). — L’espece a été décrite, en 
1877, par Hilgendorf (’77), @apres un exemplaire en médiocre état, 
acheté & Enoshima (Japon) & un marchand de coquilles locales. Cet 
échantillon a été, plus tard, figuré par E. von Martens (80, Pl. VIII) ; 
il fait, actuellement, partie des collections du musée de Berlin. 

5. Pleurotomaria Quoyana. — Exploration du “ Blake,” station 290 
(1879), au large des Barbades, 73 brasses. Cet exemplaire avait l’ouver- 
ture un peu brisée ; il était pourvu de l’animal, quia été étudié par Dall 
(89, 397, Pl. XXXI, Fig. 1). La coquille est actuellement déposée au 
U. 8. National Museum de Washington (’89, 397). 

6. Pleurotomaria Quoyana. — Exploration du “ Blake,” st. 296 (1879) 
au large des Barbades, 84 brasses.2_ Exemplaire en parfait état, avec 
Vanimal et l’opercule, déposé au Museum of Comparative Zotdlogy de 
Cambridge (U. 8.) : c’est celui qui a été étudié dans le présent mémoire. 

7. Pleurotomaria Adansoniana. — Exploration du “Blake,” st. 278 
(1879), au large des Barbades, 69 brasses. Un individu mort, brisé, 
déposé au Museum of Comparative Zodlogy de Cambridge. 

8. Pleurotomaria Adansoniana. — Exploration du “ Blake,” st. 276 
(1879), au large des Barbades, 94 brasses. Individu avec l’animal, déposé 
au U. S. National Museum de Washington, figuré par Dall (’89, PI. 
XXXVII, Fig. 4). 

Dimensions : diamétre maximum, 88 millimétres ; hauteur maximum, 
70 millimetres. 

9. Pleurotomaria Adansoniana. — Exploration du “ Blake,” st. 291 
(1879), au large des Barbades, 200 brasses. C’est un superbe échan- 


tillon, pourvu de V’animal; il a été déposé au Museum of Comparative 
Zoology de Cambridge. 


1 Voir aussi H. Crosse et P. Fischer (’72); H. Crosse (’76); A. Agassiz (’88), 
Vol. II, p. 69. 

Les figures publi¢es par Agassiz (’88) et par Dall (’89) se rapportent aux spéci- 
mens de Pleurotomaria Quoyana et de Pl. Adansoniana, dont il est maintenant 
question. 


202 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Dimensions : diametre maximum, 130 millimetres ; hauteur maximum, 
130 millimetres. 

10. Pleurotomaria Rumphii (Type). — Le type de la quatriéme espéce 
a été trouvé dans un lot de coquilles des Moluques appartenant au Jardin 
zoologique de ‘Rotterdam; c’est le plus grand de tous les exemplaires 
connus de Pleurotomaires vivants. Ila été décrit, en 1879, par Schep- 
man (’79), figuré trois ans aprés par le méme auteur (’82), et, plus 
tard, par Sowerby (’87) et par A. Pilsbry.* 

Dimensions: diamétre maximum, 190 millimétres; hauteur, 170 
millimetres, 

11. Pleurotomaria Beyrichit. — Un exemplaire en partie brisé, acheté 
en 1881 a Enoshima (Japon) par le docteur Déderlein dans une des 
nombreuses boutiques ot sont en vente, 4 titre de curiosités, des ani- 
maux marins de diverses especes (Hyalonema Sieboldi, Fusus pagoda, 
Crustacés, etc.) Cet exemplaire appartient au docteur Déderlein, 
actuellement professeur 4 Strasbourg. i 

12. Pleurotomaria Beyrichiit.—Un trés bel exemplaire, en parfait 
état, acheté & Enoshima, en avril 1881, par le docteur Déderlein & un 
pécheur japonais qui l’avait rapporté, avec d’autres especes, de Misaki 
(Japon). Ce spécimen a été communiqué ultérieurement & M. Schneider, 
de Bale, puis acheté, pour la somme de 950 marks, par Petel, qui l’a 
légué, avec sa collection, au musée de Berlin.’ 

Dimensions: diamétre, 89 millimetres; hauteur, 83 millimetres ; 
longueur de la fissure & l’ouverture, 33 millimétres. 

13. Pleurotomaria Adansoniana.—Cet exemplaire, qui était habité 
par un Pagure, fut recueilli dans une nasse 4 homard, & Vilet au Fajou, 
dans le grand cul-de-sac de la Pointe-&-Pitre (Guadeloupe), 4 150 brasses 
de profondeur. Il a été figuré, en 1882, par H. Crosse (’82, 12, Pl. I, 
Fig. 1-2) et déposé au musée Lherminier, 4 la Pointe-a-Pitre. 

14. Pleurotomaria Beyrichii, — Un bel exemplaire trés frais, acquis, en 
1882 ou 1883, par le docteur Gottsche 4 Enoshima (Japon), a été acheté 
ensuite par M. R. Damon, de Weymouth, pour la somme de 500 marks, 
puis décrit et figuré par Woodward (’85). Miss Farrington, de Preston, 
s’est rendue propriétaire de cette belle coquille et l’a léguée, avec ses 
collections, & sa sceur qui la posséde encore actuellement. 


1 Pilsbry (’90), Pl. LVIT, Fig. 13, 14, et H. Crosse (’80 et ’82°). 

2 Nouns croyons devoir rectifier une annotation de Woodward (’85, au bas de 
la page 435), qui peut préter & confusion. L’auteur, d’aprés une communication 
du docteur Gottsche, signale les deux exemplaires du docteur Déderlein comme 
incomplets et ne présentant pas la fissure, ce qui n’est pas exact, car l’exemplaire 
du musée de Berlin est intact. 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 203 


15. Pleurotomaria Beyrichit. — Un bel exemplaire, acheté 4 Londres 
par M. Sowerby, sans indication de provenance, se trouve dans une col- 
lection particuliere en Angleterre. 

16. Pleurotomaria Beyrichit. —Un exemplaire, acheté par M. Fulton 
& un négociant du Japon, fait aujourd’hui partie d’une collection par- 
ticuliere de New-York. 

17. Pleurotomaria Beyrichit.— Un autre spécimen, ayant la méme 
origine que le précédent, a été acquis, en 1895, par le U.S. National 
Museum de Washington.' 

Dimensions: diamétre maximum, 65 millimetres; hauteur, 60 milli- 
metres. 

18. Pleurotomaria Quoyana. — Exploration de U. S. Fish C. S. “ Al- 
batross,” st. 2354 (1885 ?), au large des cdtes du Yucatan, prés Arrow- 
smith Bank, 130 brasses. Un individu mort, en bon état, & part une cas- 
sure & ouverture; déposé au U. 8. National Museum de Washington. 

Dimensions : diamétre maximum, 48 millimétres; hauteur, 40 milli- 
metres. 

19. Pleurotomaria Adansoniana. — Ce magnifique exemplaire, le plus 
grand et le plus beau de l’espéce, a été remarqué, en 1890, par Lechmeer 
Guppy,” 4 lexposition de la Trinité et de Tobago. Il a été acheté par 
M. R. Damon et figuré par lui (91), puis acquis pour la somme de 55 
livres sterling par le British Museum de Londres, ot il est exposé. 

20. Pleurotomaria Beyrichit. — Un hel exemplaire, avec l’animal, a 
été péché, en 1897, au Japon, au large de Boshu, sur le banc Okinosé ; 
il fut communiqué aussitdt & M. Alan Owston, de Yokohama, et au pro- 
fesseur Mitsukuri, de Tokio, qui put Vobserver vivant.§ Ce spécimen 
est maintenant dans les collections du British Museum de Londres. 

21. Pleurotomaria Beyrichit. — Un bel exemplaire a été acquis tout 
récemment par M. Dautzenberg, de Paris. 

En résumé, les exemplaires connus se répartissent de la manitre 
suivante : 

Pleurotomaria Quoyana, 5; Pl. Adansoniana, 6; Pl. Rumphii, 1 ; 
Pl. Beyrichii, 9. 

Il est fort probable que cette liste n’est pas compléte, surtout en ce 
qui concerne le Pleurotomaria Beyrichii dont un ou deux exemplaires, 
autres que ceux mentionnés, existent encore en Europe. Il semble 
méme que cette derniere espece soit appelé & devenir moins rare que les 


1 Pilsbry (’95), W. E. Collinge (’94). 
2 Lechmere Guppy (’90 et 91), Pilsbry (92). 
3 Mitsukuri (’97). 


204 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


autres, car les pécheurs japonais en capturent de temps en temps. 
Souhaitons que les spécimens soient un jour assez nombreux pour 
permettre d’entreprendre une étude anatomique compléte de ces formes 
si intéressantes. 


Résumé de nos Connaissances sur l’Aspect Extérieur et 
lOrganisation de l’Animal. 


Une courte description de l’animal a été donnée par Agassiz (’72). 
Plusieurs figures, prises sur l’animal vivant par M. J.-H. Blake, tant de 
Pleurotomaria Quoyana que de Pl. Adansoniana, ont été publiées par 
M. Dall, qui a complété, sur bien des points, la description précédente ; 
récemment enfin, Mitsukuri (97) a publié une courte note sur l’animal 
vivant du Pl. Beyrichit. 

1° Pleurotomaria Quoyana et Pl. Adansoniana. — Dall a surtout dé- 
crit en détail le Pleurotomaria Quoyana, et les lignes suivantes se rap- 
portent spécialement & cette espéce, & moins d’indication contraire ; 
les deux formes different d’ailleurs assez peu. 

Coloration générale, téguments. — Le corps est brun rouge; de fines 
lignes sombres transversales s’étendent sur la téte, plus serrées en avant 
des tentacules qu’en arriére. Le bord du manteau est plus sombre que le 
pied. La téte, en arriere des tentacules, présente une surface rugueuse et 
ridée transversalement ; le reste du corps, & l’exception de la sole pédieuse, 
est finement granuleux ou papilleux. 

Chez le Pleurotomaria Adansoniana, la surface du corps est moins 
rugueuse que chez Pl. Quoyana. 

Pied. — Le pied, trés développé, est presque deux fois plus long que 
la coquille. Sa partie postérieure porte un opercule corné multispiré, 
semblable & celui des Trochidés,? mais de petite dimension relativement 
a la taille de la coquille. En arriére du lobe operculigére se trouve une 
surface triangulaire limitée de chaque cété par les prolongements pos- 
térieurs des lobes épipodiaux ; cette surface est légerement tuberculeuse 
chez le Pleurotomaria Quoyana, tandis que chez le Pl. Adansoniana, elle 
est sillonnée de fortes rides transversales et creusée d’un sillon médian ; 
Waprés M. Dall, c’est cette différence qui fournit le caractére le plus net 
pour séparer les deux espéces d’aprés ]’animal. 

Epipodium. — 11 est large, mince, muni, comme les bords du man- 
teau, d’une rangée de petites papilles courtes; il est dépourvu des 


1 Dall (’89, Pl. XXIX, Fig. 1; Pl. XXX, Fig. 1-6). 
2 Dall (’89, Pl. XXXII, Fig. 10). 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 205 


filaments et prolongements qu’on observe chez les Trochidés et chez les 
Scissurellidés. Sur l’animal vivant, l’épipodium est intimement appliqué 
sur le manteau, qu'il double en contournant le bord de la coquille et se 
comporte donc tout autrement que chez les Trochidés, dont ]’épipodium 
s’épanouit librement dans l’eau. Celui du Pleurotomaria Adansoniana 
est moins développé que celui du Pl. Quoyana. 

Téte. — La téte est pourvue de deux tentacules droits et pointus et 
prolongée antérieurement par un gros muffle cylindrique, dont l’ex- 
trémité, arrondie en forme de disque, porte la bouche au centre et, 
inférieurement, un sillon médian. Les yeux, situés & la base des ten- 
tacules, sont ronds, petits et noirs ; ils montrent une perforation centrale, 
de sorte que l’eau de mer occupe la place du cristallin absent et pénétre 
dans la coupe formée par le fond de ’ceil. 

Manteau. — Ses bords sont garnis de papilles, surtout le long de l’en- 
taille qui correspond & la fissure de la coquille. Lorsque l’animal est en 
extension, les deux lévres de cette entaille s’accolent, sauf 4 l’extré- 
mité interne du sinus, ot il reste une ouverture ayant le réle d’un 
siphon. 

Branchies. — Les branchies n’ont été observées que chez le Pleuro- 
tomaria Adansoniana; elles sont au nombre de deux, situées & l’intérieur 
do la cavité palléale, pres de la soudure du manteau avec le corps, et 
leur ensemble forme deux séries presque symétriques de feuillets aplatis, 
déposés de chaque céte d’un bourrelet longitudinal, & parois minces, con- 
tenant le vaisseau branchial, et qui s’étend parallélement A l’entaille du 
manteau.! L’extrémité antérieure du bourrelet est libre sur une petite 
distance et forme une pointe ow les feuillets branchiaux diminuent de 
grandeur. Chacune des deux branchies contient environ trois cent 
soixante feuillets. Dans la région ot le bourrelet devient libre, on 
observe un renflement des téguments, et, 4 cdté de lui, un petit organe 
hémisphérique qui est peut-étre sensoriel (osphradium 2). 

Appareil digestif. — M. Dall a décrit la mAchoire et la radule dont 
il sera question plus loin; il a observé, chez le Pleurotomaria Adan- 
soniana, les restes d’un jabot & parois trés minces. L’extrémité de 
Vintestin se recourbe fortement en S avant de s’ouvrir A l’anus.° 

Reins (?). —Immédiatement au-dessous de V’intestin se trouve une 
glande ou bien une paire de glandes en contact sur la ligne mé- 
diane qui paraissent s’ouvrir, prés de l’extrémité postérieure de 1’en- 
taille palléale, par deux orifices obliques et symétriques. M. Dall 

1 Dall (’89, p. 401; p. 434, Fig F; Pl. XXX, Fig. 2). 
2 Dall (’89, Pl. XXX, Fig. 8). 


206 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
suppose que ces deux glandes et ces deux orifices sont les reins avec 
leurs pores excréteurs. 

Enfin, M. Dall (’89, Pl. XXX, Fig. 3), figure, prés des orifices ré- 
naux ou supposés tels, une autre paire de pores sur lesquels il ne 
s’explique pas; peut-étre faut-il y voir des pores génitaux. 

2° Pleurotomaria Beyrichii.—Ce que nous sayons sur cette espéce 
se réduit 4 fort peu de chose: d’aprés M. Mitsukuri (’97), la sole pé- 
dieuse est jaune-paille; les cdtés du pied sont marqués de taches et 
de trainées carmin foncé sur fond orange; le muffle est rouge-carmin. 
Le tentacule gauche de l’individu observé avait une petite branche prés 
de la pointe. Les deux lobes épipodiaux se relévent jusque sur la co- 
quille, et il semble méme, d’aprés la description de auteur japonais, 
que ces lobes €épipodiaux présentent un développement considérable. 


DEUXIEME PARTIE. 
Etude Anatomique du Pleurotomaria Quoyana. 


L’animal que nous avons eu entre les mains avait été extrait de sa 
coquille, que nous n’ayons, par conséquent, pas pu examiner. L’éti- 
quette jointe a l’échantillon portait les indications suivantes : 

“U.S. Coast Survey, C..P. Patterson, Supt. Carribean Islands Ex- 
ploration. U.S.C. 5.8. ‘Blake,’ Alex. Agassiz, 1878-1879. 

“ Pleurotomaria Quoyana. 

“No, 296. Depth 73 fathoms, Barbados. 

“This is the best of the specimens and (except the operculum) is 
exactly as when it was taken from the shell.” 

L’animal a été représenté tel qu’il nous parvint dans la figure 1, 
Pl. I, du présent mémoire. Arraché avec effort de sa coquille, il avait 
perdu le tortillon tout entier, les branchies, la plus grande partie du 
manteau et des viscéres, 4 l’exception de la radule et d’une portion 
déchirée de l’cesophage et de la masse buccale. Le pied se trouvait 
intact, mais il était recroquevillé, comme le montre la figure ; le muscle 
columellaire, les tentacules, les yeux, une partie des parois de la ca- 
vité antérieure du corps et une faible partie de la région inférieure 
du manteau n’étaient pas trop endommagés et se prétaient encore 
parfaitement 4 des recherches anatomiques; 1’épipodium n’était pas 
apparent au premier abord et nous piimes croire un instant qu’il faisait 
défaut ; mais un examen ultérieur plus attentif nous a permis de le voir, 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 207 


contracté par l’alcool, 4 la partie supérieure du pied. Il parait peu 
développé et s’arréte assez loin des tentacules. 

Pour plus de détails sur la morphologie externe, nous renvoyons 
& nos figures et aux mémoires de M. Dall, que nous avons résumés 
plus haut. 


DESCRIPTION DE LA RADULE. 


M. Dall (89, 399, Pl. XXXI, Fig. 1) a décrit et figuré en partie la 
radule du Pleurotomaria Quoyana;: en plus de la dent impaire, il dis- 
tingue trois séries de dents: 1° les daterales, au nombre de vingt-six, 
plus ou moins aplaties; 2° les uncini, ayant un 4a trois denticules 
presque aussi longs que la pointe principale; les uncini situés anté- 
rieurement (wneini majores) sont plus forts et ont plus de denticules 
que les suivants (wncini minores); on compte dix-huit & vingt de ces 
uncini; 3° les Jaterales minores, tres nombreuses, petites, transpa- 
rentes et si rapprochées qu’il est presque impossible de les compter. 
M. Dall pense qu’il en existe quarante 4 cinquante; elles sont minces 
et spatuliformes, l’auteur n’a observé sur aucune de ces dents les 
touffes qu’il a décrites chez le Pleurotomaria Adansoniana. La formule 

2 2S, (aH 18 45 4 
radulaire serait donc R (+ + + ( + ri }: 

La lettre R désigne la dent rachidienne (impaire) ; les chiffres in- 
serits en dénominateur indiquent le nombre de cuspides qui caractérise 
chaque dent. 

Nous allons compléter la description de M. Dall en y apportant 
quelques modifications. 

La radule des Pleurotomaires est extraordinairement compliquée ; il 
existe peu de Mollusques qui présentent d’aussi importantes modifi- 
cations le long d’une série transversale ; mais ces modifications pré- 
sentent un remarquable caractére de continuité qu’on ne trouve a un 
pareil degré chez aucun Diotocarde; nous reviendrons d’ailleurs en 
détail sur cette particularité spéciale aux Pleurotomaires, 

Les rangées transversales n’ont nullement une direction transverse, 
mais sont repliées en forme de V. La figure 12 (Pl. III) représentant 
la radule, vue par dessous, montre cette disposition d’ensemble; il est 
clair que de ce cdté les dents ne peuvent pas tre apergues ; seules leurs 
surfaces d’insertion sont visibles. Nous avons représenté une demi-rangée 
(Pl. ITI, Fig. 1) & un plus fort grossissement, également vue par des- 
sous; on remarque que la surface d’insertion de chaque dent varie de 
forme et de grandeur depuis la ligne médiane jusqu’a l’extrémité ; c’est 

VoL. xxx11.— No. 10. 2 


208 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


& la limite du premier et du deuxiéme tiers que la base des dents pré- 
sente le plus de force. 

Nous avons pu établir le nombre exact des dents d’une rangée; il 
existe une dent médiane impaire, et, de chaque cdté, cent dix-sept dents 
paires ; on trouve, en outre, au-dela de la cent dix-septiéme dent, la 
base rudimentaire d’une cent dix-huitiéme. La forme de ces dents est 
trés variée, et, pour la commodité de la description, nous diviserons les 
dents paires en cing groupes, qui n’ont pas d’ailleurs de limites précises : 
1° dents centrales ; 2° dents lamelleuses ; 3° dents & crochets (ou uncini) ; 
4° dents @ brosses ; 5° dents flabelliformes. 

Nous désignerons chaque dent par son numéro d’ordre a partir de la 
dent impaire (exclusivement). Les dents ayant méme numéro d’ordre 
dans deux rangées différentes sont toujours rigoureusement identiques ; 
nous avons constaté le fait tres minutieusement, notamment dans les ré- 
gions de transition entre deux groupes consécutifs, ot l’on pouvait s’atten- 
dre 4 des variations individuelles; il n’en est rien; la vingt-neuvieme 
dent, par exemple, a toujours identiquement la forme figurée. 

La disposition générale des dents présente quelques particularités 
dignes d’étre signalées ; les deux moitiés ne se correspondent pas exacte- 
ment, mais il y a un léger chevauchement (PI. III, Fig. 2 et Fig. 12); 
en outre, la surface ot s’attachent les dents (épithélium lingual) est loin 
d’étre plane ; la dent impaire et ses voisines sont insérées sur une forte 
saillie longitudinale, de chaque cdté de laquelle on trouve une forte 
dépression ott sont les dents lamelleuses triangulaires. Au-dela de cette 
dépression court une nouvelle saillie qui supporte les grosses dents 
a crochet. Ces dispositions se voient facilement en examinant la radule 
par dessous. 

Dent impaire. — La dent impaire (Pl. III, Fig. 4, 5, 6), de petites 
dimensions,’ est presque couchée sur l’épithélinm lingual; elle est con- 
stituée par une lame vaguement quadrangulaire, située dans le plan 
médian, et prolongée antérieurement? par une pointe assez aigué ; elle 
s’instre sur l’épithélium lingual suivant une bande étroite et allongée 
dans le sens de la ligne médiane (cette bande d’insertion est représentée 
obliquement, vue de trois quarts, dans la figure 5); son bord postérieur, 
trés incliné, porte, de chaque cdté, deux expansions minces et foliacées, 
visibles & droite et & gauche dans la figure 5. 

1 Les dents figurées isolément sont toutes figurées au méme grossissement de 
70 diaméetres : ce sont toutes des dents du cété gauche. 

2 Dans les pages qui suivent, nous appellerons extrémité antérieure d’une demi- 


rangée de la radule, celle qui se trouve sur la ligne médiane; par exemple, la figure 
2 représente la moitié antérieure de la demi-rangée gauche. 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 209 


Dents centrales paires.— De part et d’autre de la dent impaire, les 
premiéres dents que l’on rencontre sont de beaucoup plus grande taille 
que la dent impaire et que les suivantes ; elles sont insérées (Fig. 3) sur 
une ligne a peu pres transversale; on peut les appeler les dents centrales 
paires en limitant cette région, arbitrairement d’ailleurs, anx trois pre- 
miéres. Elles sont larges et aplaties (Fig. 7, 8, 9), cest la deuxiéme 
qui présente la largeur maximum; elles portent, du cdté externe, une 
créte de renforcement qui se prolonge latéralement et inférieurement 
par une expansion mince et foliacée (Fig. 3), homologue de celles de la 
dent médiane, mais diminuant rapidement de grandeur. Leur surface 
d’insertion est concave (Fig. 7-9). 

On remarquera qu’il existe une assez brusque différence de forme et 
de taille entre la dent impaire et la premiére centrale: celle-ci n’a 
point l’équivalent de la pointe que posséde la dent impaire. Au con- 
traire, la quatriéme dent ne différe de la troisiéme que par le rétrécisse- 
ment de son extrémité supérieure. La quatriéme établit donc une 
transition tres ménagée entre les dents centrales, et les dents lamel- 
lenses ; nous n’avons, d’ailleurs, attribué 4 ces distinctions qu’une valeur 
absolument artificielle. 

Dents lamelleuses. — A partir de la troisieme dent inclusivement, la 
direction générale de la rangée change et, au lieu d’étre transversale, 
s’éloigne de l’axe suivant en angle aigu d’environ 30 degrés. La taille 
des dents diminue légérement jusqu’a la sixiéme ou septiéme (Fig. 2), 
en méme temps que la forme tend a devenir triangulaire ; entre la sep- 
tiéme et la vingt-cinquiéme la taille reste 4 peu prés constante, puis 
s’accroit rapidement au-dela. Les petites expansions foliacées qui se 
trouvent & la base des dents centrales persistent sur Jes dents lamel- 
leuses, mais disparaissent sur la vingt-neuviéme. La huitiéme et la 
vingt-huitiéme dent sont représentées sur les figures 3 (Pl. III) et 2 
CPI IY). 

Dents & crochets. — La vingt-neuviéme dent établit la transition entre 
les dents lamelleuses triangulaires et les dents & crochets. Elle” pré- 
sente encore une forme générale triangulaire (Pl. IV, Fig. 1, dent du 
milieu) et son extrémité est assez mince; d’autre part, vue de cété 
(Fig. 3), elle présente une remarquable analogie de forme avec la dent 
suivante (Fig. 4) et montre trés nettement le début de deux cuspides ; 
il est impossible de rapporter cette dent aux précédentes plutdt qu’aux 
suivantes, car elle a des caractéres exactement intermédiaires. 

Les dents 4 crochet qui suivent perdent assez rapidement la forme 
triangulaire, tout en restant aplaties latéralement ; elles s’allongent, 


210 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


s’incurvent, et leur extrémité se munit de cuspides. La trentiéme (Fig. 
4) est bicuspide, mais elle possede une faible indication d’une troisiéme 
cuspide qui va se développer sur les suivantes. La trente et uniéme 
(Fig. 6) et la trente-deuxieme sont trés caractérisées comme dents tri- 
cuspides ; on observe que le bord externe et le bord interne présente l’un et 
lautre bourrelet d’épaississement: le bourrelet interne, du cdté concave, 
forme deux des cuspides que nous appellerons euspides internes, tandis que 
le bourrelet externe, du cOté convexe, se termine par la cuspide externe. 
Dans la région comprise entre les deux bourrelets, la dent est mince et 
aplatie. La trente-troisitme (Fig. 7) ne porte plus que deux cuspides : 
la cuspide interne inférieure a avorté, et sa place n’est plus indiquée 
que par une légére ondulation du bord, dont on ne trouve méme plus de 
trace dans la trente-quatrieme. Les dents numérotées de 32 4 35 sont 
les plus fortes de toutes; ce sont aussi celles dont la base présente les 
plus grandes dimensions (Pl. III, Fig. 1). 

A partir de la trente-sixiéme, la partie recourbée de la dent diminue 
d’épaisseur ; en méme temps, le bourrelet externe de renforcement 
prend de moins en moins d’importance dans la partie terminale, en sorte 
que la cuspide externe, toujours médiocrement saillante, méme a la 
trente et uniéme dent ot elle présente son maximum de développement, 
est de plus en plus en retrait avec la cuspide interne ; en somme, la trente- 
quatriéme dent prend déja l’aspect d’une dent unicuspide, aspect qui ne 
fait que s’accentuer (Pl. 4, Fig. 21) et devient trés marqué pour la 
quarante et uniéme ; toutefois la cuspide externe, quoique pratiquement 
invisible, existe toujours morphologiquement comme terminaison émous- 
sée du bourrelet externe, toujours présent. 

La quarante-deuxiéme dent (Pl. IV, Fig. 9) est encore unicuspide, 
mais elle montre, sous la forme d’un léger renflement, le rudiment d’une 
nouvelle cuspide interne, qui se développe rapidement sur les dents 
suivantes (voir Fig. 11) et qui parait se former au méme point ot avait 
disparu la cuspide interne inférieure des trentiéme, trente et uniéme et 
trente-deuxiéme dents. Les quarante-troisiéme et quarante-quatriéme 
dents deviennent donc bicuspides, mais sont fondamentalement du méme 
type tricuspide que la trente et uniéme, en tenant compte de ce que 
nous venons de dire sur la cuspide externe. Cette structure ne tarde 
pas 4 se compliquer: la quarante-cinquiéme dent (Pl. IV, Fig. 11) 
montre, en effet, entre ces deux cuspides internes, le début d’une troi- 
siéme cuspide interne (cuspide moyenne) qui va se développer sur les 
dents snivantes (ex : 48° dent, Fig. 25), qui deviendront done tricuspides, 
mais d’un type différent des triscuspides rencontrées antérieurement, 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 211 


puisque les trois cuspides dépendent du bourrelet interne. On voit que 
la série des dents 4 crochet est loin d’étre uniforme. Les derniéres 
d’entre elles s’amincissent sensiblement. 

Dents & brosses. — La quarante-huitiéme dent fait la transition entre 
les dents 4 crochet et les dents & brosse. Le bourrelet externe est tou- 
jours présent ; mais son extrémité distale (qui équivaut a la cuspide ex- 
terne de la trente et uniéme dent) s’étant de plus en plus retirée de la 
pointe, n’arrive plus qu’au niveau de la cuspide interne inférieure et 
se termine par une sorte de petit épaississement irrégulier, qui se garnit 
de minuscules baguettes sétiformes, dont on n’observe qu’une trace a 
peine perceptible sur la quarante-huitiéme dent, mais qui forment déja 
une petite touffe sur la cinquantiéme (Pl. IV, Fig. 13). Ces soies 
sont transparentes avec une vague structure transverse ; leur diamétre 
mesure environ .002 millimétre & quelque distance’ de leur insertion. 
Leur extrémité distale est assez pointue. Sur la cinquante-septiéme 
dent, ces soies sont bien développées et atteignent l’extrémité libre de 
la dent, qu’elles dépassent méme sur les suivantes: elles se courbent 
en enveloppant l’extrémité de la dent de chaque cdté, ainsi que son bord 
convexe (Pl. IV, Fig. 27). 

La forme générale des dents 4 brosse n’est plus celle des dents a 
crochet: leur courbure est beaucoup plus faible (Fig. 15) et tend a 
s’atténuer encore en approchant de l’extrémité de la série (Fig. 16) ; 
leur tige est trés amincie. 

Les derniéres dents 4 brosse se modifient sensiblement : leurs cus- 
pides sont moins saillantes (ex: 103° dent, fig. 16); une expansion 
foliacée, latérale et externe, se développe tout du long de la tige ; elle 
est déja sensible sur la cent troisitme dent et devient extrémement 
développée vers la cent dixiéme (Pl. IV, Fig. 17) et sur les suivantes ; 
cette expansion va mSme former la totalité des dents flabelliformes, par 
suite de l’atrophie graduelle de la tige et de la brosse. 

Les cuspides paraissent disparaitre un peu avant la brosse: nous les 
avons encore apercues sur Ja cent neuviéme dent; la brosse existe 
jusqu’a la cent onziéme inclusivement, mais en s’atrophiant rapidement. 

Dents flabelliformes. — La cent douziéme dent ne présente plus trace 
de brosse: une petite incurvation du bord indique seulement sa place. 
Les derniéres dents, jusqu’A la cent dix-septiéme (Pl. 1V, Fig. 5) sont 
minces, aplaties, spatuliformes, un peu recourbées ; leurs bases sont tel- 
lement petites qu’elles prennent une disposition divergente rappellant 
assez celle des feuillets d’un éventail, dont les lames un peu courbes 
iraient en décroissant lentement. On voit sur la figure, juxtaposée a la 


212 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


base de la derniére dent, la base rudimentaire d’une cent dix-huitiéme 
dent non développée. 

Plaques basales accessoires. — Dans toute la région moyenne de chaque 
demi-série, la base des dents est accompagnée d’une petite piece acces- 
soire fortement adhérente a 1’épithélium lingual: on l’apergoit en ex- 
aminant la radule par sa face inférieure (Pl. III, Fig. 1) ou encore en 
observant l’épithélium lingual par transparence, aprés avoir enlevé 
chaque dent. La premiére plaque s’observe sur la trente-quatriéme 
dent ; il y a déja, a vrai dire, sur la trente-troisiéme, une piéce analogue, 
dun peu plus grande dimension, mais qui parait encore soudée a la 
base. A partir de la trente-quatriéme dent, cette plaque diminue un 
peu de dimension, puis augmente a partir de la trente-neuviéme ; entre 
la quarante et unieme et la soixante-quatorziéme, elle conserve a peu 
pres la méme taille et la méme forme: elle est ovale et disposée obli- 
quement ; puis elle diminue rapidement et disparait aprés la quatre- 
vingt-uniéme dent. En résumé, la radule présente une dent impaire, 
quelques dents centrales transversales, une série de dents lamelleuses, 
puis des dents a crochet, d’abord bicuspides, ensuite tricuspides, de nou- 
veau bicuspides, ensuite unicuspides, puis tricuspides, mais suivant une 
disposition différente, et, enfin, des dents flabelliformes. II existe des 
transitions ménagées entre ces divers types de dents, sauf entre la dent 
impaire et la premiere centrale. 


CoMPARAISON DE LA RADULE DES PLEUROTOMARIA AVEC CELLE DES 
AutTRES DIOTOCARDES. 


La structure de la radule du Pleurotomaria Quoyana est absolument 
spéciale et on ne trouve rien d’analogue chez les autres Scutibranches ; 
ces derniers montrent, en effet, une tendance tres nette 4 la division 
d’une série transverse en régions spécialisées ; on y distingue presque 
toujours une région centrale formée par la dent impaire et un petit nom~ 
bre de dents paires (généralement cing de chaque coté), et deux régions 
marginales (une & droite et une & gauche), constituées par des dents 
alongées et recourbées en forme de crochet ; entre la région centrale et 
chaque région marginale se trouve assez souvent une dent latérale dif- 
ferenciée, tantdt rudimentaire, tantdt, au contraire, tres forte, et qui vient 
encore accentuer la séparation des deux régions, déja bien marquée par 
les différences de structure et de grandeur des dents.* 

1 Ce schéma est parfois modifié; la dent latérale n’est pas toujours différenciée. 
En outre, les premitres marginales sont parfois différentes des suivantes ; mais, 


dans aucun cas, on n’observe de dispositions comparables & celles des Pleuroto- 
maires. 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 213 


Chez le Pleurotomaria, il y a sans doute des variations considérables 
entre les diverses dents d’une rangée, mais il est impossible de tracer des 
limites précises entre les régions qu’on peut y distinguer, car les dents se 
modifient de l’une 4 l’autre (sauf la dent impaire et sa voisine) par des 
transitions ménagées ; on voit done la différence profonde qui distingue 
les Pleurotomaires des autres Diotocardes. 

En outre, aprés les dents que nous avons appelées centrales, il existe 
une longue série de dents lamelleuses triangulaires, mal séparées des 
précédentes et dont il est impossible de trouver l’équivalent chez aucun 
autre Diotocarde ; si nous les rapportions aux dents centrales, il faudrait 
admettre, pour ces derniéres, un nombre voisin de vingt huit, c’est-a-dire 
pres de six fois le nombre (cinq) qu’on observe chez les autres Dioto- 
cardes. D’autre part, il semble impossible de les comparer aux dents 
4 crochet ; elles constituent done une série bien spéciale aux Pleuro- 
tomaires. 

Il est possible que ces dents aient avorté chez les autres Diotocardes; 
ainsi s’expliquerait la brusque différence de structure entre les dents 
centrales et les dents marginales de ces derniers. L’atrophie de la dent 
latérale chez certains genres de Trochidés,’ ot une simple lamelle rudi- 
mentaire sépare les centrales des marginales semble appuyer cette manitre 
de voir et prouve, en tous cas, que des dents peuvent disparaitre dans 
cette région de la radule. Malheureusement, cette hypothése, quelque 
satisfaisante qu’elle soit, n’est pas étayée par un nombre suflisant de faits. 

La présence des dents & brosse signalée, par Dall, chez le Pleuroto- 
maria Adansoniana et, par nous, chez le Pl. Quoyana, parait également 
caractéristique du genre. 

Il est intéressant de noter que la radule des Scissurella n’a aucun 
rapport avec celle des Pleurotomaires, mais se rattache facilement au 
type qu’on observe chez les autres Diotocardes. 

On voit que l’étude de la radule du Pleurotomaria présente un trés 
grand intérét; cet organe posséde, en effet, au moins trois caractéres 
particuliers & ce genre; transitions ménagées entre les dents d’une 
série, présence des dents lamelleuses triangulaires, dents 4 brosses. 
Le premier de ces caractéres est capital, car il est en rapport avec un 
état organisation primitif par rapport & celui des autres Prosobranches, 
chez lesquels les dents de la radule sont groupées en régions spécialisées et 
dépourvues de termes de transition. Pour mieux faire comprendre notre 
pensée, en employant une comparaison d’ailleurs tout artificielle, nous 
pouvons dire qu’on observe, chez les Pleurotomaires, quelque chose 


1 Troschel, Gebiss der Schnecken, Bd, II. 


214 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


d’analogue & ce qui se passe chez les Mammiferes fossiles les plus anciens, 
dont la dentition est remarquablement homogéne et présente des tran- 
sitions ménagées entre les dents spécialisées, incisives, canines, prémo- 
laires, etc., qui sont beaucoup mieux séparées chez les Mammiferes plus 
récents. 

MAcHOIRES. 


Les machoires ont déja été décrites par M. Dall (’89). Ce sont deux 
piéces cornées minces, trés faibles, et qui n’ont probablement qu’un réle 
fonctionnel trés restreint ; nous donnons la figure de l'une d’elles (PI. 
IIT, Fig. 2). Du bord le plus épais partent de nombreuses stries irrégu- 
lieres et serrées, qui couvrent plus de la moitié de la surface. 


ORGANES DES SENS. 


Gil. — L’eila été décrit par Dall (89, 398) et il en a été question dans 
un autre passage de ce mémoire. Nous avons vérifié, & l’aide de coupes, 
que c’est un ceil trés simple, ouvert 4 l’extérieur et tapissé & l’intérieur 
par la rétine ; son diamétre mesure environ un demi-millimetre ; orifice 
extérieur est un peu plus étroit. Nous aurions voulu savoir si sa cavité 
intérieure est absolument vide comme chez les Nautiles, ou bien si elle 
contient une substance transparente plus ou moins molle, faisant fonction 
de cristallin rudimentaire, comme chez les Zrochus ; mais le médiocre état 
de conservation ne nous a pas permis de résoudre sirement la question. 
D’apres M. Dall, il n’y a pas de cristallin et l’eau de mer pénétre libre- 
ment dans la cavité. Notons toutefois une grande analogie de forme et 
de structure avec l’ceil des Trochus.? 

Cette disposition générale de l’ceil est certainement tres primitive. 

Otocystes. — Les deux otocystes (Pl. III, Fig. 10) sont situés en avant 
et un peu au-dessus de la grosse commissure palléo-pédieuse : ils sont 
ovoides, leur plus grand diamétre mesure .55 millimetres. Leurs parois 
sont épaisses et laissent voir par transparence une cavité bourrée d’oto- 
lithes hyalins, de dimensions trés inégales, comparables par conséquent 
a ceux qui ont été décrits par M. de Lacaze-Duthiers (’72, 141) chez 
les Patella; les petits (2 » A 7 mw) sont exactement sphériques; les 
gros (jusquw’a 15 p et 20 ») sont quelquefois sphériques, mais plus fré- 
quemment ovoides allongés ou bosselés ; on ne saurait mieux les comparer 
qwaux concrétions qui se déposent concentriquement autour de plusieurs 
centres d’attraction voisins ; deux, trois ou davantage; la surface extérieure, 
au lieu d’étre une sphére, est composée de plusieurs fragments de sphere 


1 Pelseneer (’94, 59). 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 215 


qui correspondent chacun a un centre d’attraction; il semble done que 
les gros otolithes bosselés soient formés par l’accroissement de deux ou 
trois petits qui se sont accidentellement soudés. 

Le nerf acoustique, apres avoir quitté lotocyste, remonte le long de la 
corne antérieure des cordons scalariformes en adhérant trés intimement 
2 la membrane conjonctive de cette corne ; nous n’avons pas pu le suivre 
jusqu’aux ganglions cérébroides. 

Le grand nombre et l’inégalité des otolithes, ainsi que leur structure 
trés simple, viennent encore accentuer les caracteéres primitifs des Pleuro- 
tomaires ; on sait, en effet, que, chez les formes spécialiscées, les otolithes 
ont une taille uniforme, une structure plus ou moins compliquée et con- 
stante et que leur nombre subit une réduction parfois considérable. 


Systeme Nervevx.} 


Par tous ses caractéres essentiels, le systeme nerveux du Plewrotomaria 
Quoyana ressemble & celui des autres Prosobranches diotocardes, surtout 
& celui des Fissurellidés et des Trochidés ; ses ganglions cérébroides, ses 
centres stomato-gastriques, sa commissure viscérale et ses cordons palléo- 
pédieux sont construits sur le méme type; différences, qui sont toutes de 
détails, ont d’ailleurs leur importance et rapprochent, A notre avis, le 
systeme nerveux des Pleurotomaires de celui des Amphineures. 

1° Centres cérébroides (Fig. 2, 3, 8, 9, 10, C). — Les centres cérébroides 
occupent la méme place et ont la méme forme que ceux des Trochidés ; 
toutefois leur commissure est sensiblement plus large, ce qui tient 4 un 
état de condensation moins avancé des cellules ganglionnaires. Cet ¢tat 
primitif des centres cérébroides est rendu manifeste par l’étude des nerfs 
labiaux supérieurs (m1) et latéraux (m?); ces nerfs, en effet, n’ont pas 
leur origine dans les ganglions, mais, comme dans l’Haliotide sur la com- 
missure (c), au voisinage de la partie renflée des ganglions. Cette der- 
niére est triangulaire et, comme de coutume, se prolonge latéralement et 
en-dessous, sur les cétés de la masse buccale, pour former une longue 
saillie labiale (LZ); les connectifs cérébro-pédieux (k1) et cérébro- 
palléaux (4?) naissent cdte & cdte sur le bord des ganglions, en arriére 
de cette saillie. 

Sur le bord antérieur des ganglions on voit naitre, de haut en bas, 


1 Nous présentons nos vifs remerciements 2 M. le professeur de Lacaze-Duthiers, 
qui a fait recueillir pous nous, a Roscoff, de magnifiques Chiton fasciularis, & M. le 
professeur Perrier, qui nous a communiqué des Turbo radiatus recueillis par M. 
Jousseaume dans la mer Rouge. Comme on le verra plus loin, ces Mollusques 
nous ont été fort utiles pour interpréter le systtme nerveux des Pleurotomaires. 


216 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


trois nerfs labiaux (m,° m,* m®) aussi puissants que les deux premiers; 
le troisieme se détache de la saillie labiale dans sa région basilaire qui 
est trés renflée ; plus inférieurement, cette saillie émet encore un autre 
nerf labial (m°), puis se rétrécit beaucoup et devient alors purement 
fibreuse ; elle forme alors la commissure labiale (c) qui ne présente rien 
de particulier. 

Sur la face externe des ganglions cérébroides prend naissance le puis- 
sant nerf tentaculaire (t*) ; il émet, prés de sa base, une petite branche 
nuquale et, un peu plus haut, le nerf optique (f). Ilva sans dire que ce 
dernier est simplement accolé au nerf tentaculaire, mais qu’il n’est point 
fusionné avec lui. 

2° Stomato-gastrique. — Comme chez tous les Diotocardes, le systeme 
nerveux stomato-gastrique a son origine sur le bord postérieur de la 
saillie labiale (Z?) A une faible distance de sa base; comme dans ces 
derniers aussi, ses connectifs (£) sont allongés, remontent latéralement 
sous les muscles dans les flancs de la masse buccale, et envoient, chemin 
faisant, quelques ramuscules nerveux (s°) & ce dernier organe. 

La partie ganglionnaire (Fig. 12) présente la forme normale caracté- 
ristique du groupe, celle d’un fer 4 cheval. Mais ici, le fer 4 cheval ne 
présente pas les renflements prononcés qu’on observe chez les Trochidés 
et méme chez certains Chitons (Fig. 6 et 7), et qui indiquent d ja un 
commencement de condensation ganglionnaire ; 4 son origine connectivale, 
il est un peu dilaté, mais, partout ailleurs, son diamétre est sensiblement 
le méme. 

Les nerfs stomato-gastriques nous ont paru plus gros et moins nom- 
breux que chez les autres Diotocardes; nous n’avons pas pu tous les 
sulivre, en raison du mauvais état de la masse buccale, mais nous croyons 
avoir observé l’origine de tous, soit sur l’animal, soit en préparations 
microscopiques. En dehors des ramuscules issus des connectifs, ils sont 
de chaque cété au nombre de trois: deux (s*, s*) se détachent du ren- 
flement antérieur et correspondent vrai-semblablement aux nerfs que 
Yun de nous a désignés par les lettres s* et s* dans le Turbo (Bouvier, 
’87, Fig. 5), l’autre (s) se détache du bord postérieur du fer & cheval, au 
voisinage de son millieu, et doit étre l’équivalent des nerfs s* et s* du 
méme animal. L’un (s*) des deux nerfs antérieurs se dirige en arriére 
et correspond aux trois nerfs (s*) des Turbo; il est tres volumineux 
et parait renfermer des cellules nerveuses. Le nerf postérieur se bifurque 
peu aprés son origine. 

3° Connectifs issus des ganglions cérébroides et commissure viscérale 
(Fig. 3, 8, 9, 10, 11).—Issus du bord postéro-inférieur des ganglions 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 217 


cérébroides, le connectif cérébro-palléal (k*) et le connectif cérébro-pédieux 
(&1) descendent, en divergeant, dans la dépression profonde produite en 
avant par la cavité du corps (Fig. 3); lg connectif cérébro-palléal est 
en arriére et le connectif cérébro-pédieux en avant; le premier est plus 
puissant que le second. 

A droite les deux connectifs atteignent leur maximum d’écartement 
vers le tiers supérieur de leur longueur ; 4 gauche ils divergent sur une 
plus grande étendue, mais, comme du coté droit, se rapprochent ensuite 
peu A peu, et viennent aboutir dans les cornes proximales (Fig. 9 et 10, C") 
que forment avant leur réunion les cordons palléo-pédieux. Chemin 
faisant, les connectifs envoient quelques branches nerveuses aux parois 
du corps; les connectifs cérébraux-pédieux en émettent au moins deux 
(e, 6, 0’) et les connectifs cérébro-palléaux une (c, c+). Ces derniers, 
d’ailleurs, présentent le caractere tout particulier de donner naissance, 
sur leur trajet, & la branche correspondante de la commissure viscérale. 
A droite, la branche sus-intestinale (h) se détache du connectif cérébro-pal- 
léal (£*) au point ow celui-ci s’écarte le plus du connectif cérébro-pédieux, 
cest-A-dire & une faible distance du ganglion cérébroide droit (C). <A 
gauche, la branche sous-intestinale (h*) se détache plus bas du connectif 
cérébro-palléal (£*) un peu au-dessous du millieu de ce dernier. Quoiqu’il 
eu soit, on observe ici ce fait unique, chez les Gastéropodes, d’une commis- 
sure viscérale issue, non point des centres palléaux, mais des connectifs 
qui réunissent les ganglions cérébroides & ces centres. 

4° Cordons palléo-pédieux (Fig. 4, 8, 9, 11). — Chez les autres Gas- 
téropodes diotocardes (voir Fig. 5 et 13), chaque cordon palléo-pédienx 
se prolonge proximalement, au-dessus de la grosse commissure, par une 
corne ganglionnaire palléale (C”) qui se continue avec les connectifs (k?, £7) 
issus du cerveau, et la commissure viscérale vient aboutir dans une autre 
corne (Cg, Cd.) qui provient de la bifurcation de la premiére. Dans le 
Pleurotomaria Quoyana, il n’en est plus de méme : la corne (C') de chaque 
cordon, fort grosse et trés allongée, ne se bifurque pas et ne donne pas 
naissance a la commissure viscérale ; elle se dirige obliquement en arritre 
et en haut et les connectifs (k1, k*) issus du cerveau viennent aboutir a son 
extrémité supérieure. 

D’ailleurs, ces cornes ganglionnaires ne sont pas exclusivement de na- 
ture palléale ; sur leur face externe (Fig. 4 et 11) elles sont creus¢ées 
d'un sillon profond (s) qui les divise en deux rubans superposés ; le ruban 
supérieur (Ps) continue exactement le connectif cérébro-palléal (4?) 
correspondant, et le ruban inférieur (Pi) le connectif cérébro-pédieux 
(k"). Tl est done manifeste que les cornes du Pleurotomaire, au lieu 


218 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


d’étre exclusivement palléales, sont de nature mixte, que la bande supé- 
rieure est de nature palléale et l’inférieure de nature pédieuse. C’est ce 
que prouve, du reste, l’étude des nerfs qui émanent de cette région ; les 
nerfs (a, a’, a’) issus du ruban supérieur se rendent, en effet, dans les 
muscles qui forment le plancher de la cavité antérieure du corps, et qui 
sont nettement columellaires, ceux qu’émet le ruban inférieur, s’enfoncent, 
au contraire, dans la musculature du pied ou dans Ja paroi du corps. 

Or, s’il est impossible de contester la nature mixte des cornes proxi- 
males des cordons pédieux, il faut en conclure que les cordons sont 
mixtes, comme les cornes elles-mémes. En effet, le profond sillon que 
nous avons constaté sur la face externe des cornes se prolonge manifeste- 
ment, sinon sur toute la longueur des cordons, au moins sur une grande 
étendue de ces derniers; il apparait méme, mais beaucoup moins nette- 
ment, sur leur face interne (Fig. 11). Comme les cornes proximales, 
chaque cordon se trouve dés lors partagé en un ruban supérieur qui 
continue le ruban palléal des cornes et en un ruban inférieur qui 
continue leur ruban pédieux. 

Aiusi, les deux rubans de chaque cordon, en effet, ne sont certaine- 
ment pas de nature identique, du moins au point de vue de leurs rap- 
ports et de leurs fonctions. La preuve en est encore dans la position 
des commissures qui les relient d’un cété 4 ’autre et dans la nature des 
nerfs qu’ils émettent. 

Les cordons se dirigent d’avant en arriére dans le pied (Fig. 9), ot 
ils figurent presque un ovale trés peu convexe. Au point ou ils se 
continuent avec les cornes, ils sont unis par une commissure puissante 
(Fig. 11, 2), a la fois ganglionnaire et fibreuse, qui s’étend entre les deux 
rubans de chaque cété. Plus en arriére se trouvent d’autres commis- 
sures exclusivement fibreuses; nous en avons pu réparer neuf ;? mais 
leur nombre est certainement plus considérable. Elles sont moins régu- 
liérement transversales que la premiére et émettent des ramuscules qui 
se rendent dans la sole pédieuse. Ces commissures sont done vraiment 
de nature pédieuse; d’ailleurs, dans le Pleurotomaire, comme dans les 
Fissurelles, les Haliotides et les Trochidés, elles paraissent indépendantes 
des rubans supérieurs et rattachent l’un a |’autre les rubans inférieurs. 
Ce fait prouve, 4 notre avis, que les deux rubans de chaque cété ne sont 
pas de méme nature. 

Un autre fait vient encore rendre plus évidente cette maniére de voir. 


1 Ces commissures sont représentées dans la figure 9; en arriére de la neuvieme, 
les coupes nous en ont fait voir cing autres, ce qui porterait & quatorze le nombre 
des commissures accessoires. 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 219 


Comme dans les autres Diotocardes 4 cordons divisés en deux parties 
par un sillon, le ruban supérieur et le ruban inférieur émettent des 
nerfs qui n’ont pas la méme distribution. Ainsi que lont montré 
M. de Lacaze Duthiers dans )Haliotide (’59), M. Boutan (’86) dans la 
Fissurelle et le Parmophora, M. Béla Haller dans divers Diotocardes 
(’84, 20, Fig. 2), les rabans supérieurs envoient des nerfs (a, a°, a*,) en 
avant dans les parois du corps, plus en arriére dans la partie supérieure 
du pied, qui est de nature columellaire, ainsi que dans l’épipodium qui 
lorne de ses franges. Toutefois, dans notre Pleurotomaire, nous n’avons 
pu suivre ces nerfs jusqu’a l’épipodium, réduit et recroquevillé, de 
Vanimal. Entre les nerfs antérieurs issus des rubans supérieurs des 
cordons, et ceux qui proviennent du connectif cérébro-palléal ou du 
ruban qui lui fait suite dans les cornes, il y a tous les passages et le 
champ de distribution est le méme, comprenant les parois latérales du 
corps et tout ce qui, de pres ou de loin, fait partie de la région collu- 
mellaire. Tout autre est la distribution des nombreux nerfs issus des 
rubans inférieurs des cordons; ces nerfs () se rendent dans la sole 
inférieure du pied et sont manifestement de nature pédieuse; en 
outre, comme chez les autres Diotocardes, les deux nerfs Jes plus an- 
térieurs (p’) sont trés gros et se rendent dans la partie antérieure du 
pied. 

En résumant ce qui précéde, on voit: 1° que les cordons palléo-pédieux 
sont le prolongement direct de leurs cornes antérieures; 2° que les deux 
rubans qui les constituent de chaque cété sont aussi les prolongements 
directs des rubans des cornes ; 3° que les rubans supérieurs sont la con- 
tinuation des connectifs cérébro-palléaux et les rubans inférieurs la con- 
tinuation des connectifs cérébro-pédieux ; 4° que, dans les cordons comme 
dans les cornes, les rubans supérieurs envoient des nerfs aux parois du 
corps, au muscle columellaire ou & ses dépendances, tandis que les rubans 
inférieurs donnent surtout des nerfs exclusivement pédieux ; 5° enfin 
que les rubans supérieurs paraissent indépendants l’un de l'autre, en 
arriere de la commissure antérieure, tandis que les rubans inférieurs 
sont réunis par de nombreuses commissures d’od partent des rameaux 
pédieux. 

En conséquence, nous croyons pouvoir dire que les cordons, comme 
les cornes qui les terminent, sont de nature mixte, que leur partie 
inférieure est pédieuse, et que leur partie supérieure est pallcale, en 
donnant au mot palléal une signification étendue et que nous préciserons 
plus loin. 

La structure mixte des cordons est rendue tres manifeste par la 


220 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


présence de certains nerfs (pn) qu’on voit se détacher sur leur face 
externe et qui sont mixtes dans leur nature, comme le montrent les 
coupes, ou, plus simplement, un examen a la loupe. Ces nerfs sont 
surtout communs et faciles & observer dans la partie antérieure des 
cordons; quand on examine ceux-ci par la face externe, on voit que 
leur sillon est interrompu, de distance en distance, par des saillies 
linéaires obliques qui prennent leur origine dans les rubans supérieurs, 
se dirigent vers les rubans inférieurs, et, aprés les avoir atteints, se 
fusionnent, pour former un nerf, avec une racine nerveuse émanée de ces 
derniers. Ces nerfs mixtes se rendent dans le plan moyen du pied, et, 
bien que nous n’ayons pu suivre leur trajet jusqu’au bout, doivent avoir 
une distribution mixte, certains de leurs ramuscules se rendant a la 
partie supérieure et columellaire du pied, les autres dans sa partie infé- 
rieure ou pédieuse. L’existence de ces nerfs prouve, une fois de plus, 
que des parties contigués, mais de nature différente, peuvent confondre 
leurs organes d’innervation tout en restant distinctes dans leur origine 
et dans leur distribution. I] en est de méme des nerfs acoustiques: 
dans le Pleurotomaria Quoyana, par exemple, les octocystes (0) sont situées, 
comme dans les autres Diotocardes, sur le bord antérieur de la grosse 
commissure pédieuse (2), oi un tractus fibreux les réunit, aussi les ners 
acoustiques (01) se confondent-ils avec les connectifs cérébro-palléaux, et 
il nous a méme été impossible, dans notre animal, de les suivre jusqu’aux 
ganglions cérébroides, oi ils‘ prennent pourtant leur origine. Cette loi 
a été rendue parfaitement évidente par M. de Lacaze-Duthiers (’72) en 
ce qui concerne les nerfs acoustiques des Gastéropodes, mais l’étude du 
systéme nerveux des Mollusques en fournirait sans difficultés d’autres 
exemples. 

5° Commissure viscérale, nerfs palléaux (Fig. 3, 8, 9, 11). — Ainsi que 
nous l’avyons fait remarquer plus haut, les branches de la commissure 
viscérale ont une origine connectivale qu’on n’observe nulle part ailleurs 
chez les Gastéropodes, et qui donne au systeme nerveux du Plewrotomaria 
Quoyana un aspect des plus caractéristiques. La branche sus-intestinale 
(z) se détache du connectif cérébro-palléal (A?) 4 une faible distance du 
ganglion cérébroide droit ; elle se dirige en arriére en suivant la paroi 
dorsale du corps, puis se recourbe progressivement 4 gauche et passe 
au-dessus du jabot de l’animal. Dans notre animal, cet organe était 
en mauyais état et réduit & ses parois déchirées et affaissées ; au point 
oi s’effectua la rupture quand on arracha le Mollusque de la coquille, 
s’¢taient produites des lésions qui, heureusement, n’avaient pas enlevé 
la branche nerveuse; nous avons pu la suivre jusqu’au point ot 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. ye | 


les parois dorsales du corps cessaient d’exister, comme l’indique la 
figure. 

Quant & la branche sous-intestinale (h") elle se détache beaucoup plus 
bas du connectif cérébro-palléal gauche (47), nous l’avons vu se diriger a 
droite sous le tube digestif, muis elle était rompue 4 peu pres au niveau 
de ce dernier. 

En tous cas, nos recherches sont suffisantes pour établir que les Pleu- 
rotomaires possedent, comme les autres Prosobranches, une commissure 
viscérale croisée. 

Nous avons été moins heureux dans notre étude des nerfs palléaux 
proprement dits, et c’est une lacune que nous sommes les premiers a 
déplorer. Ordinairement ces nerfs sont volumineux et d’une dissection 
des plus faciles, au moins 4 leur origine; ici, nous ne sommes pas 
certains de les avoir apercus; 4 droite, nous ne voyons rien qui puisse 
leur correspondre ; mais, 4 gauche, nous considérons comme nerf pallcal 
une branche nerveuse (Fig. 8, m) qui se détache du connectif cérébro- 
palléal presque au méme point que la commissure viscérale. Au reste, 
comme on peut s’en convaincre en jetant un coup d’eil sur la figure 1, 
qui représente lanimal tel qu’il nous fut communiqué, c’est a peine si 
notre Pleurotomaire présentait les restes de la partie inférienre du man- 
teau, et nous nous demandons si les déchirures n’auraient pas arraché, 
jusqu’’ leur racine, les grands nerfs palléaux. Si l’on considére cette 
hypothése comme improbable, et nous convenons qu’elle en a toutes les 
apparences, il faut admettre que nous n’avons pas su apercevoir, au 
moins 4 droite, les vraies origines palléales. On sait que, chez les autres 
Diotocardes, les grands nerfs palléaux se détachent des cornes palléales 
supérieures ou dans le voisinage de celles-ci.* 

De la branche sus-intestinale de la commissure viscérale, nous n’avons 
vu naitre qu’un nerf assez gréle (Fig. 3 et 8, d), qui se rendait en arriére 
dans les téguments dorsaux. De la branche sous-intestinale naissaient 
deux nerfs columellaires postérieurs (1, 0"), dont Pun était trés volumineux. 
Entre le point ot elle se détache du connectif cérébro-palléal gauche et 
la corne palléo-pédieuse correspondante, cette branche est trés volumi- 
neuse ; nous avons vu quelle émet, au premier de ces points, un nerf 
assez puissant (Fig. 8 et 9, m), qui plonge, & gauche, dans les parois du 
corps, et qu’on doit considérer, 4 notre avis, comme un nerf pall&éal 
gauche. 

1 Peut-étre faut-il considérer comme les nerfs palléaux deux gros nerfs (Fig. 


11, a?, al”) qui naissent des rubans supérieurs un peu en arriére de la commissure 
palléo-pédieuse. 


222 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


Nature pes Centres Nervevx pu Prep cHEZ LES GASTEROPODES. 


Les faits qui précédent nous paraissent propres 4 jeter la lumiére sur 
un point de l’histoire naturelle des Mollusques qui a soulevé les plus 
nombreuses et les plus vives controverses, nous voulons parler de la 
nature des cordons ganglionnaires du pied des Diotocardes et de l’éten- 
due que présentent les centres palléaux de ces Gastéropodes. Sans 
vouloir remonter au début de cette controverse, ce qui n’aurait aucune 
utilité, nous dirons que M. de Lacaze-Duthiers (’59, ’90), et, a sa suite, 
MM. Wegmann (’84) et Boutan (°86, ’88, ’90, ’98) considérent les cordons 
du pied des Diotocardes comme formés par la fusion, suivant leur 
longueur, des centres palléaux et pédieux de chaque cété, tandis que 
MM. Spengel (’81), Béla Haller (84, ’89, 94), Thiele (’90) et Pelseneer 
(87, 788, 790, 791), les regardent comme franchement pédieux et con- 
sidérent comme centres palléaux les cornes ganglionnaires qui les précé- 
dent et qui donnent naissance 4 la commissure viscérale et aux nerfs 
palléaux. Abstraction faite de la nature de l’épipodium, sur laquelle 
nous reviendrons plus loin, les arguments essentiels fournis par les 
premiers sont les suivants: 1° les cordons du pied sont divisés en deux 
rubans superposés par un sillon externe; 2° le ruban inférieur est en 
relation avec le connectif cérébro-pedieux et le ruban supérieur, plus ou 
moins directement, avec le connectif cérébro-palléal et les nerfs palléaux. 
Les arguments de la partie adverse sont essentiellement tirés de l’exis- 
tence d’un vrai ganglion palléal chez les Diotocardes, ganglion qui se 
trouve dans la région proximale des cordons, en avant de la grande 
commissure antérieure; si lon admettait, disent-ils avec M. Pelseneer, 
que ces ganglions se continuent dans le ruban supérieur des cordons, il 
faudrait admettre aussi que les ganglions palléaux sont commissurés, ce 
qui n’existe pas chez les Mollusques. Les arguments de second ordre 
seront signalés plus loin. 

Pour notre part, nous croyons que la premiére théorie est l’expression 
exacte de la vérité, mais que la seconde est loin de s’en éloigner, au fond, 
autant qu’on pourrait le croire. Commengons @’abord par préciser, aussi 
exactement que possible, le sens qu’on donne communément au terme 
de palléal ou & son équivalent, celui de plewral, en anatomie comparée 
des Mollusques. 

Si l'on s’en tenait 4 I’étymologie méme des mots palléal ou pleural, on 
devrait réserver les noms de ganglions palléaua ou de ganglions pleuraux 
aux ganglions qui président 4 innervation du pallium ou manteau et 
des parois du corps des Mollusques. Mais, en réalité, ces termes ont di, 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 223 


par la force des choses, recevoir une signification plus large. Chez les 
Gastéropodes, oa les ganglions palléaux (ganglions pleuraux) sont bien 
distincts — et c’est le cas chez tous les Monotocardes—ces ganglions 
donnent naissance aux nerfs du manteau ou vrais nerfs palléaux, a cer- 
tains nerfs des parois antérieures du corps et 4 certains nerfs des muscles 
columellaires. Qu’il y ait ou non communauté d’origine entre ces der- 
niéres parties, il est certain que les nerfs qui les innervent présentent des 
caractéres communs, non seulement 4 cause de leur origine dans un méme 
centre, mais aussi en raison des anastomoses qu’ils contractent fréquem- 
ment ou de leur champ de distribution, qui est mixte: le plus souvent, en 
effet, sinon toujours, on voit les nerfs palléaux envoyer des rameaux dans 
les parties du muscle columellaire et des parois du corps qu’ils traversent. 
Quoi qu’il en soit, il ressort de ce qui précede que le champ d’innervation 
des centres palléaux appelés aussi centres pleurauz, est des plus vastes et 
s’étend bien au-dela du manteau proprement dit ou des parois du corps. 

1° Pleurotomaires. — Ceci dit, revenons au Pleurotomaire. L’intérét 
essentiel de ce curieux Gastéropode, c’est qu’il ne présente pas, comme 
les autres Diotocardes, de corne palléale distincte en avant des cordons 
ganglionnaires du pied ; de sorte que, si l’on interprétait au sens étroit 
la théorie de M. Haller et de M. Pelseneer, il faudrait dire que le Pleu- 
rotomaire est dépourvu de centres palléaux. A priorz, cette interprétation 
est inexacte, car notre Mollusque a un manteau, un muscle columellaire 
et des parois du corps aussi développées que les Haliotis ou les Trochus, 
de sorte qu’il doit avoir comme eux, c’est évident, des ganglions et des 
nerfs palléaux. Aussi bien, nous voulons rejeter cette interprétation, 
que seul, peut-étre, M. Thiele’ pourrait accepter, et nous croyons entrer 
tout a fait dans les vues de MM. Haller et Pelseneer, en disant que les 
centres palléaux sont formés, en partie du moins, par le ruban supérieur 
(Fig. 4 et 11, Ps) de la corne unique, qui prolonge proximalement de 
chaque cété les cordons pédieux. Nous avons vu, en effet, que ce ruban 
est le prolongement direct du connectif cérébro-palléal (47) et qu’il émet, 
par l'intermédiaire de ce connectif, la commissure viscérale, des nerfs 
pariétaux, des nerfs palléaux proprement dits et des nerfs columellaires. 
Quant au ruban inférieur (Pi), qui se continue par le connectif cérébro- 


1 Thiele (92), en effet, ne considere point comme des centres palléaux les 
cordons latéraux des Chitons, mais il les assimile au plexus épipodial de 1’Haliotide, 
sans d’ailleurs en donner de raison sérieuse. Pour lui, les ganglions palléaux se 
développeraient ultérieurement chez les Prosobranches. Cette opinion, qu’aucun 
auteur n’a pu adopter, est en contradiction manifeste avec les faits signalés dans 
le présent mémoire. 

VOL. Xxx1I. — No. 10. 3 


224 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


pédieux (k'), aucun fait ne saurait nous permettre de le considérer 
comme palléal, et ses connexions indiquent manifestement qu’il est de 
nature pédieuse. 

Nous voici, dés lors, en présence de cornes ganglionnaires (c’) qui sont 
mixtes a tous égards, palléales dans leur ruban supérieur et pédieuses dans 
leur ruban inférieur. Or, chacune de ces cornes est le prolongement 
@’un cordon ganglionnaire du pied, et chacun des rubans qui les compose 
est le prolongement du ruban correspondant de chaque cordon. Si les 
cornes sont palléales dans leur partie supérieure et pédieuses dans leur 
partie inférieure, tout semble des lors indiquer qu’il en est de méme des 
cordons. En fait, c’est ce que montre également l’étude des nerfs émis 
par les rubans qui constituent chacun d’eux. Ainsi qu’on le savait 
depuis longtemps, et comme on peut s’en convaincre par les figures qu’a 
données M. Béla Haller (’84, 38, Fig. 4), le pied des Diotocardes et des 
autres Gastéropodes se compose de deux parties: lune, supérieure, qui 
est formée par les fibres musculaires antérieures du muscle columellaire 
et qui recouvre les cordons; l’autre, inférieure, qui constitue la sole 
pédieuse. Or les nerfs issus du ruban supérieur se rendent dans la 
partie supérieure du pied, et, comme il est facile de s’en convaincre par la 
dissection des nerfs les plus antérieurs des cordons, dans sa partie colu- 
mellaire ; tandis que les nerfs émis par le ruban inférieur se rendent en 
divers points de la sole pédieuse. En d’autres termes, le ruban supérieur 
des cordons innerve la zone’ columellaire comme le ruban supérieur des 
cornes, dont il est impossible, d’ailleurs, de le séparer; il est dés lors, 
comme lui, de nature palléale. 

Ainsi dans le Pleurotomaire, chaque cordon du pied se compose d’un 
cordon de nature palléale et d’un cordon de nature pédieuse, de sorte 
que ces centres ganglionnaires sont mixtes, sinon de leur naissance & 
leur extrémité, au moins sur une grande partie de leur étendue.? 

Ceci étant établi, et la grosse commissure des cordons réunissant aussi 
bien les rubans supérieurs que les rubans inférieurs, il faut conclure de 
ce qui précéde que les centres palléaux sont commissurés au méme titre que 
les centres pédieux. C’est un fait contre lequel, dans le Pleurotomaire, du 
moins, il nous parait difficile de s’élever. II n’est done pas juste de 
prétendre, avec M. Pelseneer (’88, 91) que les ganglions palléaux ne sont 


1 Tl est possible, en effet, que la partie palléale ne s’étende pas jusqu’au bout des 
cordons, et c’est ce que sembleraient indiquer les centres pédieux des Fissurellidés. 
Pour étre fixé sur ce point, il faudrait ¢tudier l’exacte distribution des fibres du 
muscle columellaire et connaitre le point précis ot s’arréte le sillon en arriére. 
Cette observation s’applique & tous les Diotocardes. 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 225 


jamais commissurés ; sans doute, la commissure qui réunit les ganglions 
n’est jamais distincte de la commissure pédieuse, mais les recherches sur 
la structure intime des centres nerveux des Gastéropodes permettent 
d’établir qu’il existe, dans la commissure pédieuse, des fibres, qui se ren- 
dent aux ganglions palléaux transversales. Au reste, l’exemple du 
Pleurotomaire suffirait, 2 lui seul, pour montrer quw’il en est ainsi, 
méme si l’on admettait que la partie palléale de ce mollusque se limite 
au ruban supérieur des cornes. Dans ce cas, en effet, le centre palléal 
des cornes s’arréterait au niveau de la grosse commissure des cordons, 
et, comme le montrent les coupes, recevrait quand méme des fibres de 
cette commissure. 

2° Fissurellidés, Haliotidés, Trochidés. — Le systéme nerveux des 
Diotocardes primitifs différe surtout de celui des Pleurotomaires, par 
la présence de deux cornes proximales (Fig. 5 et 13), a l’extrémité an- 
térieure de chaque cordon du pied, l’une supérieure (Cg, Cd), que chacun 
s’accorde & reconnaitre comme palléale et qui sert de point de départ aux 
branches de la commissure viseérale ; l’autre inférieure (C1), & laquelle 
aboutissent les connectifs cérébro-palléaux et cérébro-pédieux. Ces deux 
cornes ont été désignées par M. Béla Haller (84, 17) sous le nom de centres 
pleuro-cérébraux, le méme auteur donne le nom de centre pleural ou com- 
missural, c’est-a-dire de centre palléal,’ 4 chaque corne supérieure ; mais, 
comme il passe outre sur les cornes inférieures, on doit croire, sinon qu’il 
les tient tout entieres pour pleurales, du moins qu’il ne leur attribue, 
a aucun degré, la nature pédieuse. Au surplus, il est nécessaire de rap- 
peler que les partisans de la théorie des cordons pédieux simples ne 
cherchent pas & caractériser la nature des cornes inférieures; M. Béla 
Haller les a bien figurées, mais M. Pelseneer, qui a consacré le plus de 
travaux & la question, ne les mentionne méme pas, et, pourtant, elles 
sont trés développées dans les Fissurelles ('86, Pl. XX XV), dans les 
Cemoria (Haller, ’94, Fig. 142, voir Pl. II, Fig. 13), un peu moins dans 
certains Turbo (Fig. 95) et Trochus ; dans les Haliotides, elles sont A 
peine sensibles. Or, toutes les fois qu’elles existent, ces cornes ser- 
vent, comme dans les Pleurotomaires, de point d’arrivée aux connectifs 
eérébro-palléaux et cérébro-pédieux, et, comme chez ces derniers aussi, 
elles sont parcourues par un sillon longitudinal et divisées en deux 
rubans qui continuent ceux des cordons du pied. Ces rubans et ce sillon 
se voient surtout bien dans la Fissurelle, ainsi qu’il résulte des figures de 


= 


1 Spengel (’81) a donné le nom de ganglions pleuraur aux centres que nous 
appellons ganglions palléaux ; M. von Ihering les nomme aussi ganglions commis- 
suraux ('77). 


226 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


M. Boutan (’86, Fig. 10, Pl. XX XV), et, comme ils ressemblent en 
tout A ceux des Pleurotomaires, comme les cordons offrent avec eux 
les mémes rapports, il y a lieu, croyons-nous, de leur accorder la méme 
signification. 

Toutefois, il existe ici une différence importante, qui est précisément 
la cause de la controverse qui nous occupe; une partie de la substance 
palléale des cornes et des cordons s’est accumulée & l’origine de la com- 
missure viscérale pour former des ganglions palléaux déja distincts sous 
la forme de cornes supérieures, en méme temps qu’une partie de la sub- 
stance pédieuse des cornes inférieures se concentrait dans le ruban infé- 
rieur des cordons. De lA le développement réduit des cornes inférieurs 
des Fissurelles, Turbo, Trochus, etc., qui sont beaucoup moindres que les 
cornes uniques des Pleurotomaires. 

Ainsi, chez les animaux qui nous occupent, le systeme ganglionnaire 
palléal tend & se localiser en deux masses: l'une antérieure, qui s’isole 
et émettra des nerfs pour les parties palléales de la région antérieure du 
corps; l’autre, en contact sur toute sa longueur avec les centres pédieux, 
qui desservira une partie des parois du corps, et surtout la partie du 
muscle columellaire qui forme les plans supérieurs du pied. Aux nerfs 
issus de cette partie palléale située dans le pied, M. Béla Haller a donné 
le nom de nerfs latérauzx, ils se rendent, dit-il, dans les parois du corps, 
et les plus antérieurs dans le muscle columellaire (84, 21). 

3° Patellidés, Néritidés, Cyclophoridés, Paludinidés, Cypreidés. — Le 
processus de concentration, dont nous venons de voir un exemple dans 
les formes précédentes, s’accentue davantage encore chez les Patellidés, 
chez les Néritidés et chez certains Monotocardes primitifs (voir p. 238, 
Fig. E). Les ganglions palléaux destinés aux parties palléales de la 
région antérieure du corps (manteau, partie du muscle columellaire la 
plus voisiue de la coquille, une partie des parois du corps) se séparent de 
plus en plus des cordons et forment les ganglions palléaux proprement 
dits ; ils s’isolent ainsi du ruban palléal supérieur, qui restera logé dans le 
pied, au voisinage immédiat des parties qu’il innerve (parois les plus an- 
térieures du corps, parties du muscle columellaire situées dans le pied). 
Des lors, les rubans pédieux et palléaux de chaque cordon, destinés & 
innerver des parties contigués se fusionnent et se concentrent de plus en 
plus, leur sillon de séparation s’efface, et l’on arrive ainsi & des cordons 
simples en apparence, mixtes en réalité, auxquels tous les auteurs ont 
donné le nom de cordons pédieux, bien qu’ils renferment une partie pal- 
léale et une partie pédieuse. Ces cordons ne different guére de ceux des 
Diotocardes primitifs que par l’atrophie de leurs cornes inférieures, l’isole- 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 2aL 


ment plus grand de leurs cornes supérieures appelées ganglions palléaus, 
la disparition de leur sillon et la moindre quantité de cellules palléales 
qu’ils renferment. Pour le reste, tout est semblable, et la fusion dont 
leurs deux parties constituantes ont été le siege n’est rien autre chose 
que le résultat de la concentration de centres ganglionnaires contigus, 
concentration dont les exemples abondent dans l’histoire des Gas- 
téropodes.* 

4° Autres Gastéropodes. — Des formes précédentes on passe sans diffi- 
culté, par une concentration plus grande encore, aux Gastéropodes 
dépourvus de cordons ganglionnaires dans le pied (voir p. 238, Fig. F). 
Les ganglions palléaux proprement dits se séparent nettement de la 
région pédieuse, et les cordons de cette derniére se condensent d’arriere 
en avant pour former les ganglions pédieux, arrondis ou ovoides, des 
divers auteurs. Mais ces prétendus ganglions pédieux sont mixtes, en 
réalité ; ils innervent, comme on sait, les parties pédieuses et columel- 
laires du pied et n’ont point perdu toute relation avec les ganglions pal- 
léaux proprement dits. Ces derniers, en effet, comme chez Je Pleuroto- 
maire et les Diotocardes, sont commissurés & travers les ganglions et la 
commissure pédieuse. Il y a longtemps qu’on s’était apergu de ce fait, 
et Walter en a donné un bel exemple dans ses études micrographiques 
sur le systeme nerveux de la Lymnée (’63, Taf. IV, Fig. 1) ; on trouve 
quelque chose d’analogue dans le travail de M. Garnault (’87, Fig. 32) 
sur le Cyclostome. 

En résumé, nous pensons, avec MM. de Lacaze-Duthiers et Boutan, 
que les cordons du pied des Fissurelles, des Haliotides, des Turbo et des 


1 Dans son travail les organes glandulaires d’Helcion pellucidam L. (Lottia pel- 
lucida), M. Boutan (’98, 472) cherche a établir que le systtme nerveux de cette 
espece est un terme de passage entre le systtme nerveux des autres Patellidés et 
celui du Parmophore. Pour établir ce fait, qui serait au moins singulier, M. 
Boutan reproduit en schéma la belle figure du systtme nerveux de |’Helcion qu’a 
donnée M. Haller (’94, Fig. 1) et en fait une sorte de syst®me nerveux de Chiton ow 
la commissure viscérale croisée serait surajoutée. C’est interpréter trop librement, 
selon nous, le texte et les figures de M. Haller; l’énorme cordon ganglionnaire, 
semblable & celui des Chitons, que représente M. Boutan dans son schéma, n’a pas 
son équivalent dans la figure de M. Haller, ou du moins il ne s’y trouve qu’a I’état 
de nerfs palléaux fusionnés en arritre, comme on l’observe fréquemment chez les 
Patellidés. Ces nerfs, il est vrai, renferment quelques cellules ganglionnaires, mais 
le fait n’est point rare dans l’innervation palléale des Mollusques, et c’est vraiment 
exagérer que de transformer en cordons palléaux de Chitons, les nerfs palléaux des 
Patellidés. L’interprétation de M. Boutan n’est done pas fondée, mais le fit-elle, 
ce n’est pas entre les Patellidés et les Fissurellidés que devraient se placer les 
Heleion, mais bien entre les Chitons et les Pleurotomaires. 


228 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Troques, sont palléaux dans leur partie supérieure, pédieux dans leur 
moitié inférieure; avec MM. Haller, Pelseneer, Thiele, etc., qu’ils sont 
les homologues des cordons pédieux des Patelles, des Nérites, des Cyclo- 
phores, des Paludinés, des Cyprées, et des ganglions pédieux de tous les 
autres Gastéropodes, abstraction faite de la masse ganglionnaire palléale 
un peu plus abondante qu’ilsrenferment. Nous differons des uns et des 
autres en attribuant une nature mixte, a la fois palléale et pédieuse, aux 
centres ganglionnaires (ganglions pédieux de tous les auteurs), condens¢s 
ou non, qui envoient des nerfs a la masse musculeuse complexe qu’on 
désigne sous le nom de pied chez tous les Gastéropodes. Les Pleuroto- 
maires se distinguent de tous les autres Mollusques de la classe en ce que 
la masse ganglionnaire palléale ne tend pas encore d isoler sa partie 
antérieure, et reste en relation, dans toute son étendue, avec la masse 
ganglionnaire pédieuse. 


NATURE DE L’EPIPoDIUM DES PROSOBRANCHES. 


La comparaison des Diotocardes avec les Pleurotomaires et les Mono- 
tocardes nous ayant conduit a établir la nature mixte des cordons ou des 
ganglions qui se rendent au pied des Gastéropodes, il nous est facile 
maintenant d’interpréter comme il convient la frange pariétale connue 
sous le nom d’épipodium qui borde la partie supérieure du pied, chez 
la plupart des Diotocardes et chez certains Monotocardes tels que la 
Janthine. 

Il est un fait bien établi par tous les auteurs, c’est que les nerfs de 
lépipodium sont précisément les nerfs latéraux de MM. Béla Haller 
(’84, 20) qui naissent du ruban supérieur du cordon palléo-pédieux. 
M. de Lacaze-Duthiers l’a, depuis longtemps, montré dans |’ Haliotide 
(759), plus réceemment, M. Boutan a observé la méme disposition chez 
la Fissurelle, (’86) et M. Béla Haller (’84, 94) chez les Diotocardes qu’il 
a étudi s. 

M. Pelseneer (’90, 91), qui a consacré plusieurs mémoires 4 cette 
question, ne met pas en doute ce fait, mais il en conteste la valeur en 
objectant que les nerfs de la partie antérieure de |’épipodium chez les 
Diotocardes, partent du connectif cérébro-pédieux et que, parmi ceux de 
la partie postérieure, certains sont mixtes et prennent & la fois leur origine 
dans les deux rubans des cordons. Pour ce qui est du premier point, 
lobservation de M. Pelseneer est exacte, mais n’a pas l’importance que 
lui attribue cet auteur. Si l’épipodinm “ était palléal, dit M. Pelseneer, 
il est bien évident que, dans cette région, il devrait étre innervé partiel- 
lement par le connectif cérébro-pleural.” Cet argument ne nous parait 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 229 


pas fondé, car les connectifs sont formés de fibres nerveuses, et ne 
peuvent des lors, donner naissance 4 des nerfs. I] s’agirait de savoir si 
les fibres épipodiales qui se détachent des connectifs cérébro-pédieux 
prennent naissance dans le ruban supérieur ou dans le ruban inférieur 
du cordon et, jusqu’ici, personne ne nous a fixés sur ce point. Mais si 
l’on observe que les nerfs épipodiaux postérieurs se détachent tous du ru- 
ban supérieur, il y a des raisons pour croire que ceux issus des connectifs 
cérébro-pédieux prennent aussi leur origine dans le méme ruban et que 
s'ils émergent des connectifs prévédents, c’est que ceux-ci sont externes 
par rapport aux connectifs cérébro-palléaux et, par conséquent, plus 
rapprochés de l’épipodium. II] ne faut pas oublier, en effet, que les nerfs 
se rendent, par la voie la plus directe, 4 leur champ de distribution par- 
ticulier et, ici, cette voie ne saurait étre que celle des connectifs cérébro- 
pédieux. Si, comme l’affirme M. Thiele (’92), certains nerfs épipodiaux 
paraissent se d tacher des ganglions cérébroides, leur origine réelle devrait 
étre, & notre avis, dans le ruban supérieur des cordons. 

Quant aux nerfs épipodiaux qui, d’apres M. Pelseneer, prendraient 
leur origine 4 la fois dans les deux rubans de chaque cordon, il y a lieu 
de croire que ce sont des nerfs mixtes, dont certaines branches se rendent 
a ’épipodium et d’autres dans les parties avoisinantes de la sole pédieuse. 
La dissection de toutes les branches d’un nerf du pied étant des plus 
pénibles, il ne sera pas facile de donner des arguments pour ou contre 
cette maniére de voir; mais ce qu’il y a de bien certain, c’est que, chez 
les Diotocardes trés primitifs, tels que les Pleurotomaires, les nerfs 
mixtes sont beaucoup moins concentrés que dans les autres formes du 
groupe, et présentent encore au dehors deux racines, l’une qui se détache 
du ruban inférieur, ’autre qui émerge du ruban supérieur. 

Chez les Janthines, ainsi que l’un de nous (Souvier, ’86, 91, Pl. III, 
Fig. 2) la établi, les nerfs de l’épipodium naissent tous des deux ganglions 
pédieux et paraissent dés lors étre de nature exclusivement pédieuse. 
Mais cette apparence n’est point d’accord avec la réalité: Jes nerfs de 
l’épipodium des Janthines sont les plus supérieurs du pied, comme ceux 
de la partie columellaire pédieuse, et sont dés lors de nature palléale 
comme ces derniers. Cela revient 4 dire, comme nous I’avons établi 
précédemment, que les ganglions du pied sont de nature mixte, A la fois 
palléaux et pédieux. 

Nous laissons de cété les formations latérales des Patellidés gu genre 
Lottia (Helcion) qui sont innervées par le cordon pédieux. M. Pelseneer 
(90, 152) tient ces formations pour épipodiales, mais M. Béla Haller 
(94, 73-76) et tout récemment M. Boutan (’98) ont établi qu’elles sont 


230 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


de nature glandulaire et sans homologie aucune avec l’épipodium. Fit- 
elle méme épipodiale, son innervation par les cordons du pied ne prouve- 
rait nullement la nature exclusivement pédieuse de |’épipodium, car les 
cordons du pied sont, nous l’avons dit, 4 la fois palléaux et pédieux. 

De ce qui précede, il résulte qu’on doit, avec MM. de Lacaze-Duthiers 
et Boutan, considérer l'épipodium des Prosobranches comme étant de 
nature palléale, en donnant & ce mot la signification que nous lui avons 
attribuée précédemment. Tant qu’on n’aura pas établi qu’il provient 
d’un dédoublement du manteau, on ne pourra pas dire que l’épipodium 
a la méme origine et la méme nature que ce dernier, mais il est au moins 
pleural comme le manteau luicméme, comme le muscle columellaire et 
comme les régions des parois du corps qu’innervent les ganglions palléaux 
isolés. 

Un mot encore, pour en finir avec cette question de l’épipodium. 
D’apres MM. Béla Haller et Pelseneer, la division des cordons du pied 
des Diotocardes en deux rubans superposés serait due & la présence des 
nerfs épipodiaux qui se détachent de la partie supérieure des cordons, 
tandis que les autres nerfs du pied prennent naissance dans leur partie 
inférieure. 

Pour nous, cette s paration des deux sortes de nerfs montre tout sim- 
plement que les deux rubans des cordons sont des centres ganglionnaires 
distincts et la preuve, c’est que le sillon qui les sépare n’est nulle part 
plus accentué que chez le Pleurotomaria Quoyana, espece dont l’épipodium 
est, comme on sait, tres peu développé. Si la séparation des rubans 
atteint son maximum chez les Prosobranches les plus primitifs, en dépit 
de leur épipodium trés réduit, c’est que, selon toute vraisemblance, ces 
rubans ne sont autre chose que des centres ganglionnaires primitivement 
séparés qui se sont rapprochés peu a peu, et ont fini par se fusionner suivant 
leur longeur. Au début, la ligne de démarcation des deux sortes de centres 
s'est trouvée indiquée par un sillon large et profond, puis la concentration 
s’accentuant, le sillon a disparu peu & peu, en méme temps que sisolait 
en avant UNE PARTIE de la substance ganglionnaire palléale sous la forme 
de ganglions palléaux distinets. 


ORIGINE DU SystkME NERVEUX DES PROSOBRANCHES, 


Si lon se demande maintenant quels sont les Mollusques dont le 
systéme perveux a pu, en se modifiant, servir de point de départ & celui 
des Diotocardes, on est conduit 4 considérer les Amphineures, et princi- 
palement les Chitonidés, comme étant les formes qui se rapprochent le 
plus de ces Mollusques. 


| 
| 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS, Zou 


Systeme nerveux des Chitonidés et des Diotocardes. —Comme les Dio- 
tocardes, en effet, les Chitonidés (voir p. 233, Fig. A) sont pourvus de 
cordons ganglionnaires palléaux et de cordons pédieux, qui présentent 
entre eux et avec les ganglions voisins les mémes relations essentielles. 
Ainsi que nous avons pu nous en convaincre par la dissection du Chiton 
fascicularis Poli et de |’ Acanthopleura Savatiert Rochebr., les cordons 
ganglionnaires pédieux des Chitonidés s’étendent parallélement sur toute 
la longueur du pied, ils émettent les nerfs pédieux proprement dits et 
sont mis en relation par des commissures transversales plus ou moins 
irréguliéres dont certaines se bifurquent parfois et envoient des branches 
dans la sole pédiense. Ces faits ont été mis en évidence par M. Béla 
Haller (782), mais nos observations different de celles qu’a publiées cet 
auteur en deux points qui mériteut d’étre signalés: le premier, c’est 
que la commissure pédieuse antérieure est, comme |’a montré M. von 
Ihering (’77, 45, Fig. 4), plus volumineuse que les autres et réguliére- 
ment transversale ; le second, c’est que chaque cordon pédieux se rat- 
tache aux centres cérébroides du méme cété par un prolongement qui 
s’atténue réguliérement d’arriére en avant. Ce prolongement anasto- 
motique est muni de cellules nerveuses comme les cordons, mais, con- 
trairement aux observations de M. Béla Haller (’82, Fig. 1) sur le Chiton 
siculus Gray, il est plus gréle que les cordons, surtout dans sa partie 
antérieure qui se rattache aux centres cérébroides; c’est un connectif 
cérébro-pédieux encore riche en cellules ganglionnaires, et, si lon rap- 
proche de ce fait l’existence d’une commissure pédieuse grosse et régu- 
liérement transversale, on trouve que les cordons pédieux des Chitonidés 
sont semblables, & tous égards, aux rubans pédieux des Diotocardes, 
surtout a4 ceux des Pleurotomaires et des Fissurelles, cordons qui se 
prolongent en avant de la grosse commissure, comme on sait et se con- 
tinuent progressivement avec les connectifs cérébro-pédieux. 

Mémes homologies entre les cordons palléaux des Chitonidés et les 
rubans palléaux des Pleurotomaires. Ils donnent naissance, comme 
eux, aux nerfs du manteau et des muscles columellaires, et, comme eux 
aussi, envoient des branches aux viscéres; bien plus, chaque cordon 
palléal se met en relation avec le cordon pédieux du méme cdté par des 
anastomoses transverses trés nombrenses. La présence de ces anasto- 
moses est d’une grande importance pour éclaircir le probléme qui nous 
occupe; elle montre que les cordons pédieux et palléaux des Chitonidés 
ne sont pas plus indépendants que ceux des Diotocardes, et qu’il suffira 
d’un raccourcissement progressif des anastomoses palléo-pédieuses pour 
que les cordons pédieux et palléaux de chaque cété arrivent A se con- 


232 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


fondre et forment des cordons palléo-pédieux semblables 4 ceux des Dio- 
tocardes. Les anastomoses palléo-pédieuses sont trés nombreuses chez 
certains Amphineures vermiformes ou elles ont été mises en évidence 
par M. Hubrecht (’81, ’82) dans la Proneomenia Sluiteri Hubr. ; M, von 
Ihering en avait trouvé une de chaque cété dans le Chiton salamander 
(77, Fig. 47) et M. Béla Haller dans le Chiton fascicularis (’82, 11, 
14); mais, depuis, M. Plate (95%, 796) et M. Thiele ('95) ont mis 
en évidence, chez divers Chitonidés, un ensemble d’anastomoses aussi 
riche que celui des Proneomenia, et nous avons observé le méme fait 
dans le Chiton fascicularis. 

Plus frappantes encore, si c’est possible, sont les ressemblances et les 
homologies qui existent dans la partie antérieure du systeme nerveux chez 
les Chitonidés et les Diotocardes. Les centres cérébroides des Chitons, 
il est vrai, sont moins condensés et émettent des nerfs sur toute leur 
partie commissurale, mais on sait que la concentration des mémes gan- 
glions est loin d’étre compléte chez les Diotocardes et que I’ Haliotide, 
& ce point de vue, ressemble singuliérement aux Chitons. Au reste, les 
homologies qui nous occupent ne portent pas seulement sur la structure 
générale du systéme, mais s’étendent jusqu’a ses détails: les saillies 
labiales des Chitonidés ont la méme forme et la méme origine que celles 
des Diotocardes, et, comme chez ces derniers, donnent naissance 4 la 
commissure labiale (Fig. A, ce’) et 4 un certain nombre de nerfs labiaux ; 
le systeme stomato-gastrique a la méme forme caractéristique dans les 
deux groupes et se trouve au méme état de concentration imparfaite, il 
occupe la méme position sur les parois de la masse buccale et, fait plus 
remarquable encore, prend ses origines (£) au méme point sur la saillie 
labiale des centres cérébroides. D’aprés M. Béla Haller (94, Fig. 1), 
on retrouverait méme, chez les Patellidés, les ganglions subradulaires 
qu’on observe chez tous les Chitons. 

Ayant montré les homologies étroites qui existent entre le systéme 
nerveux des Chitonidés et celui des Diotocardes, il nous reste 4 inter- 
préter les dissemblances qu’on observe dans le méme systéme, entre les 
deux groupes. La plus importante, celle qui, 4 vrai dire, domine et 
comprend toutes les autres, c’est la forme et I’étendue particuliére du 
systéme ganglionnaire palléal chez les Chitonidés. Grace a la position 
du manteau qui, sous la forme d’une frange épaisse, entoure le corps des 
Chitonidés et passe juste au-dessus de la bouche et de I’anus, le systéme 
ganglionnaire palléal des Chitonidés forme un anneau allongé parfaite- 
ment clos qui passe lui-m@me, comme le manteau, au-dessus de la bouche 
et de ’anus. Produit par une concentration nerveuse trés peu accen- 


‘ 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 233 


tuée, cet anneau palléal a conservé des relations étroites avec les centres 
nerveux voisins: en arriére de la région céphalique, nous avons vu qu’il 


se rattachait aux cordons pédieux 
par de nombreuses anastomoses ; 
dans la région céphalique, 4 cause 
de la superposition du manteau et 
des lévres, l’anneau s’est fusionné 
avec les centres cérébroides et ne / 
s’en distingue plus que par un sillon LY 
(Fig. A., s.). M. von Ihering (77, Ra 
44, Fig. 4) s’est parfaitement rendu sf See 
compte de cette coalescence et, ae 
avant tout autre, s’est efforcé de ‘Sem 
mettre en évidence la nature com- 
plexe des centres ganglionnaires an- 
térieurs des Chitons. Nous ne voy- 
ons pas pourquoi M. Béla Haller 
(82, 4) a essayé de combattre une 
opinion aussi juste; il suffit de jeter 
un coup d’cil sur le systéme ner- 
veux d’un Chiton pour acquérir la 
conviction que M. von Ihering a dit 
vrai. Bien plus, les figures de M. 
Béla Haller (’82, Fig. 32) établis- 
sent elles-mémes manifestement que 
le systeme nerveux céphalique des 
Chitonidés se compose de deux cen- 
tres différents dont l’un innerve ex- 
clusivement le manteau, tandis que 
Yautre envoie une rangée de nerfs Fie. A.—Systeme nerveux du Chiton 
aux lobes céphaliques et une se- Jascicularis. — P nerfs palléaux; s sil- 
conde a la région labiale. Nous ne oe m fee ie ieeinege - 
¢ ; a partie antériéure des centres pal- 
faisons allusion & la coupe repré- léaux ; k origine du stomato-gastrique ; 


seutée dans la figure 32 du mémoire R ganglions subradulaires. (Dans 
cette figure et dans les cing suivantes 


de M. Béla Haller sur les Chitons 

de VAdriatique ; quant Bes figure 1 les centres cérébroides sont marqués de 

ers t i elle’ a ey traits verticaux ||], les centres pédiaux 
me travail, elle donne Vidée go traits horizontaux = et les centres 

la plus fausse des relations qui ex- _palléaux de ponctuations..... ) 


istent entre les centres antérieurs 
et la partie libre des cordons palléaux, car les nerfs des lobes céphaliques 


V 


| 


= 
ANE CAT 


ANS 


LUM STVOMMCT HAS RANGA NUL ent TU EAE 


AABATEACG 


ae 


SY 
oy 


nm 


Drv stannic 

D 

Morr f 
z 


234 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


(nerfs 2 de l’auteur) y paraissent naitre du ruban qui continue les cor- 
dons palléaux, tandis que les nerfs palléaux (nerfs 1 de l’auteur) et les 
nerfs labiaux prendraient leur origine dans la partie des centres anté- 
rieurs qui continue les cordons pédieux. C’est tout le contraire de ce 
que lon observe en réalité, quand on étudie les Chitonidés.! Au reste, 
des traces manifestes de la disposition particuliére au systeme nerveux 
de ces derniers se rencontrent chez les Gastéropodes ; dans ces derniers, 
en effet, des fibres nerveuses de la commissure cérébroide traversent les 
centres cérébroides eux-mémes, et, par les connectifs cérébro-palléaux, se 
rendent aux ganglions palléaux (voir Walter, ’63, Pl. IV, Fig. 1; de 
Nabias, ’94, 14, Pl. IV, Fig. 79). 

Une autre différence entre le systeme nerveux palléal des Chitonidés 
et celui des Diotocardes, c’est l’absence, chez les premiers, de toute com- 
missure viscérale. Comme les Diotocardes, les Chitonidés émettent des 
nerfs branchiaux et viscéraux issus du systéme palléal, mais ces nerfs ne 
se rattachent pas a une anse viscérale fermée et vont séparément se 
rendre aux organes qu’ils desservent. C’est, nul ne le conteste, un état 
primitif auquel a dti faire suite un état ot certains nerfs viscéraux s’ana- 
stomosaient d’un cdté 4 lautre par-dessous l’intestin; toutefois, on n’a 
rien observé jusgu’ici, chez les Chitonidés, qui montrat le début de 
ces anastomoses. M. von Ihering avait cru trouver cette commissure 
primitive, dans le Chiton cinereus (’77, Fig. 4); mais il avait pris pour 
elle la commissure subradulaire, dont les origines ne sont pas, comme 
il le croyait, sur les cordons palléaux. Depuis, M. Haller a signalé dans 
le Chiton fascicularis (’82) et dans le Ch. magnificus (’94*) une paire 
de nerfs palléaux antérieurs qui viendraient se fusionner dans des gan- 
glions sous la partie antérieure de l’estomac; mais les recherches de 
M. Thiele (95) et de M. Plate (95, ’95%, 96), quoique portant sur de 
nombreux Chitonidés, n’ont pas confirmé cette découverte, et les re- 
cherches les plus minutieuses nous ont conduits aux mémes résultats 
négatifs que ces derniers. Malgré ces observations déconcertantes, tous 
les auteurs admettent, et nous admettons avec eux, que la commissure 
viscérale primitive a dfi se produire par un procédé analogue et former 

1 La méme figure ayant été relevée dans presque tous les ouvrages classiques, il 
y a lieu de signaler, croyons-nous, les autres corrections qu’elle demande; 1° la 
commissure pédieuse antérieure est plus forte que les autres; 2° les connectifs céré- 
bro-pédieux s’atténuent au lieu de se dilater au voisinage des centres cérébroides ; 
3° la saillie labiale ne se détache pas de ces connectifs, mais bien des centres céré- 
broides; 4° les racines du systeme nerveux subradulaire se trouvent sur le bord 


postérieur de la saillie labiale; 5° de nombreuses anastomoses transversales rat- 
tachent les cordons pédieux aux cordons palléaux. 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 235 


une anse sous-intestinale anastomotique, qui reliait entre eux les cordons 
palléaux. Les Chitonidés sont assez variables dans leur structure (Voy. 
Plate, 96, 176) pour qu’on puisse espérer y découvrir quelque jour les 
débuts de cette anse commissurale. 

Modifications progressives du systeme nerveux des Amphineures et 
des Gastéropodes. — Puisqu‘il est impossible de contester les homologies 
profondes qui existent entre le systéme nerveux des Chitonidés et celui 
des Gastéropodes primitifs, il nous faut indiquer maintenant le pro- 
cessus par lequel a di passer le premier pour former le second. Quelle 
que soit l’idée que l’on se fasse du systéme branchial des Chitonidés, ou 
des formes voisines qui ont servi de point de départ aux Diotocardes, on 
doit admettre, avec M. Biitschli (’87) et les autres zoologistes que ce 
systeme était réduit & deux branchies chez les Diotocardes primitifs, 
que ces deux branchies étaient situées en arriere 4 droite et 4 gauche de 
Vanus, qu elles étaient innervées par l’anse viscérale primitive dont nous 
avons parlé plus haut, et que l’ensemble de ce complexe anal s’est dé- 
placé progressivement & droite et a fini par se placer en avant du coté 
dorsal, dans une cavité palléale située en arriére de la région céphalique. 
On sait que le résultat de ce déplacement a été la torsion en 8 de chiffre 
de la commissure viscérale chez les Prosobranches, et (ainsi que l’un de 
nous l’a montré (Bouvier, 92, ’93) et comme M. Grobben (’94) et 
M. Pelseneer (’94) Pont reconnu dans la suite) que les Gastéropodes 
& systéme nerveux orthoneure dérivent des Prosobranches diotocardes 
par un retour, vers sa position primitive, du complexe anal, et par la 
distorsion de la commissure viscérale qui a été la conséquence de ce 
déplacement rétrograde. 

Ceci dit, nous allons examiner les divers stades qu’a dii suivre le sys- 
téme nerveux chitonien des Gastéropodes primitifs, des Praerhipidoglosses 
comme les appelle M. Plate (95), pour arriver 4 se transformer en un 
systéme nerveux typique de Gastéropode. 

Premier stade. (Fig. B).— Le manteau recule en arriére de la téte, qui 
fait de plus en plus saillie en avant, ce qui a pour conséquence de séparer 
complétement des centres cérébroides, les cellules ganglionnaires palléales 
qui formaient un ruban sur leur bord dans les Chitons ; il se forme ainsi, 
de chaque cété, un connectif cérébro-palléal & peu prés dépourvu de 
cellules et les cordons palléaux, grossis dans leur partie antérieure, se pro- 
longent plus ou moins sur ces connectifs. A l’autre extrémité du corps, 
la chambre qui renferme les deux branchies devient de plus en plus pro- 
fonde, les cordons palléaux s’arrétent 4 l’extrémité antérieure de cette 
chambre dont les bords sont innervés par deux nerfs anastomoses qui 


236 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


sont Jes prolongements, 4 peu prés dépourvus de cellules nerveuses, des 
cordons palléaux. Telle est V’origine des nerfs palléaux primitifs ; des 
branches nerveuses moins puissantes partent aussi de la commissure 
viscérale pour se rendre dans le manteau. En méme temps, la coquille 
gagne en importance, les muscles columel- 
laires se développent et se superposent au 
pied, dont ils constituent la partie supé- 
rieure. Les muscles columellaires et pédi- 
eux forment, de plus en plus, un ensemble 
morphologique distinct, et, par un raccour- 
cissement progressif des anastomoses pal- 
léo-pédieuses, les centres ganglionnaires de 
ces muscles se rapprochent de plus en 
plus. — La forme orthoneure, qui réalise 
ce type, ne nous est pas connue; inter- 
médiaire entre les Chitonidés et les Dio- 
tocardes, elle devait avoir un systéme 
nerveux peu concentré et différait par 
conséquent beaucoup du Preerhipidoglosse, 
a ganglions condensés, tel que l’a con¢u 
M. Plate. 

Deuxiéme stade (Fig. C).— La cavité 
-palléale est plus profonde et vient peu a 
peu se placer dorsalement en arriére de 
la t€te, ce qui ameéne le croisement de la 
commissure viscérale et le déplacement en 
avant de ses racines, qui sont issues, 
comme on sait, des cordons palléaux. 
Grace au processus de condensation qui 
continne, ces derniers ont fini par se fu- 
Fic. B. — Systéme nerveux sionner, suivant leur longueur, avec les 

hypothetique intermédiaire gordons pédieux, pour former, de chaque 
aa po OD cdté, entre les muscles pédieux et une 
P nerfs palléaux; A anus. partie des muscles columellaires, un cor- 
don unique ow ils apparaissent, l’un sous 

forme de ruban palléal, ’autre sous la forme de ruban pédieux séparé 
du premier par un profond sillon. Au reste, la condensation ganglion- 
naire, dans le sens de la longueur, est encore fort peu avancée, et les 
deux rubans se prolongent en une corne, en avant de la grosse commis- 
sure des cordons, jusqu’aux connectifs cérébro-pédieux et eérébro-palléaux. 


id 


ToT 


aca 
es ge AW 


ehriels l 


‘ 
; 
} 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. Zar 


Le Pleurotomaria Quoyana se trouve précisément au stade que nous 
venons de signaler. 

Troisiéme stade (Fig. D). — Ce stade ne différe du précédent que par 
la condensation plus grande de tous les centres nerveux, et, dans bien 
des cas, par l’atrophie de la branchie droite des Pleurotomaires. Du 
ruban supérieur de chaque corne des cordons, et probablement des par- 
ties voisines de ces derniers, se sépare une corne dorsale exclusivement 


nin 


penn atta 
. 


Sk. 


MMT Ls a 


Fae 
Ha 


a 


Fie. C.—Systéme nerveux du Fie. D.—Systéme nerveux 
Pleurotomaria Quoyana. dialyneure des Trochidés. 


palléale ; des deux cornes qui se trouvent, dés lors, en avant de chaque 
cordon, celle qui est située du cdté dorsal tend de plus en plus A grandir 
et a s'isoler, tandis que la corne ventrale se réduit progressivement, tant 
par le passage de sa partie palléale dans la corne dorsale, que par la 
condensation en arriére du ruban pédieux qui la compose. En méme 
temps s’atténue le sillon qui sépare les deux rubans de chaque cordon. 
Les Fissurellidés, Haliotidés et Trochidés se trouvent a ce stade: leurs 


238 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


nerfs palléaux d’origine commissurale sont assez peu importants, mais 
s’anastomosent déja avec les nerfs palléaux primaires. 

Quatriéme stade (Fig. E). — Les rubans palléaux et pédieux de chaque 
cordon se fusionnent complétement et l’on ne voit plus trace des sillons 
qui les séparent ; les cornes ganglionnaires dorsales forment des ganglions 
palléanx plus ou moins isolés et les cornes ventrales ont disparu. Les 
Patellidés, les Néritidés, les Hélicinidés, les Paludinidés, les Cyclo- 
phores et les Cyprées sont a ce stade. 


Fic. E.— Systeme nerveux Fic F.— Systéme nerveux zygoneure 
presque zygoneure du Cyclo- du Triton. 
phorus. 


Cinquietme stade (Fig. F).— Les cordons palléo-pédieux se conden- 
sent suivant leur longueur et forment des ganglions palléo-pédieux ovoides, 
plus connus sous le nom de ganglions pédieux ; les cornes palléales 
deviennent des ganglions palléaux trés distincts qui se rapprochent de 
plus en plus des centres cérébroides, du moins dans la majorité des cas. 
En méme temps, on voit, chez les Prosobranches, les nerfs palléaux 
secondaires contracter des anastomoses de plus en plus étroites avec les 
nerfs palléaux primaires correspondants, ce qui conduit & la zygoneurie. 
Chez les Gastéropodes orthoneures, le complexe anal revient du cété 
droit, et la distorsion du systeme nerveux se produit & divers degrés. 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 239 


Telle est, croyons-nous, lidée la plus nette et la plus exacte que l’on 
puisse se faire de l’évolution du systéme nerveux chez les Gastéropodes. 
Muni de cordons pallév-pédieux profondément sillonnés et dépourvus de 
cornes palléales distinctes le Pleurotomaria Quoyana se trouve & un stade, 
inconnu jusquw’ici, qui permet de concevoir tous les autres et qui rap- 
proche singuligrement les Gastéropodes archaiques des Amphineures, 
dont ils paraissent tirer leur origine. 

An reste, ce n’est point seulement par son systeme nerveux que le 
Pleurotomaria Quoyana se place, avant tout autre, en téte des Mol- 
lusques Gastéropodes. Avec ses branchies presque rigoureusement 
symétriques et ézales, ses orifices rénaux (et génitaux?) également pairs 
et symétriques, sa radule 4 régions mal délimitées, ses yeux en cupule 
ouverte & Vextérieur, et ses nombreux otolithes toujours petits et de 
dimensions inégales, il fait songer aux formes les plus primitives du 
groupe et permet de concevoir, mieux que par le passé, les formes plus 
primitives encore dont les Diotocardes sont issus. 

Il est & présumer que des recherches anatomifques entreprises sur 
d’autres especes du genre viendront combler les lacunes nombreuses que 
laisse forcément notre travail, et étendre plus sirement le champ de 
généralisation que nous avons ouvert. A ce propos, qu’il nous soit per- 
mis de signaler aux zoologistes l’intérét tout particulier qui s’attache aux 
origines de la commissure viscérale chez les Pleurotomaires ; situées sur 
les connectifs cérébro-palléaux dans le Pleurotomaria Quoyana, elles 
sont certainement fort curieuses et ne ressemblent gueére a celles des 
autres Gastéropodes. Mais avant de chercher la raison de ces origines 
remarquables et d’en tirer parti pour expliquer l’origine des Gastéro- 
podes, il faut @tre bien certain qu’elles ne sont pas spécifiques et se- 
condaires, mais primitives et caractéristiques du genre. C’est un point 
important, sur lequel nous fixeront bientét, il y a lieu de l’espérer, 
d’autres anatomistes. 


VOL. XXXII. — no. 10 4 


240 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY, 


INDEX BIBLIOGRAPHIQUE. 


1° Partie SPECIALE (HisTORIQUE). 
Férussac. 

21. Tableaux systématiques des animaux Mollusques, Pl. XXXIV. 1821 (?). 
Cet ouvrage fait partie de Histoire générale et particulitre des Mollusques 
terrestres et fluviatiles, publié a partir de 1819. 

Sowerby, J. 
721. Mineral Conchology, Vol. III. p. 189, T. CCLX XVIII, décembre 1821. 
Borson. 

21. Saggio di orittografia piemontese (Memorie della Reale Accademia delle 

Scienze di Torino, T. XX VI, 1821, Pl. II. Fig. 1). 


Defrance. 
23. Dictionnaire des sciences naturelles, planches, 2 partie; Regne organisé. 
Zoologie, conchyliologie et malacologie, par M. Ducrotay de Blainville, 26° 
cahier, Pl. LXXXVI, Fig. 2 et 3. 
Defrance. ; 
°24. Tableau des corps organisés fossiles, p. 114. 
Defrance. 
°26. Dictionnaire des sciences naturelles, par plusieurs professeurs du Jardin 
du roi et des principales écoles de Paris, T. XLI, 1826, p. 381 (Pleuroto- 
maria). 
Sowerby, J. 
°31. The Genera of Recent and Fossil Shells, Part XX XII (fin de Pannée 1830 
ou commencement de 1831). Pleurotomaria, avec une planche coloriée. 
Sowerby, J. 
44, Mineral Conchology, Vol. VII, p. 69, T. DCXL, novembre 1844. 
Fischer, P., et Bernardi. 
56. Description d’un Pleurotomaire vivant (Journ. de Conchyl., T. V, 1856, 
p. 160-166, Pl. V, Fig. 1-3). 
Adams, H., et A. 
58. ‘The genera of Recent Mollusca, London, Vol. LI, p. 630. 
Ryckholt, De. 
60. Revue des genres qui composent la famille des Haliotide (Journ. de 
conchyl., T. VIII, 1860, p. 183). 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 241 


Crosse, H., et Fischer, P. 
*61. Observations sur le genre Pleurotomaire et Description d’une deuxitme 
espece vivante appartenant au méme genre (Journ. de couchyl., T. IX, 
1861, p. 155-167; Pl. V, Fig. 1 et 2). 
Schramm. 
69. Catalogue des Coquilles et des Crustacés de la Guadeloupe, 2° édition, 
Basse-Terre, 1869, p. 9. 
Woodward, S. P. 
°70. Manuel de conchyliologie, Paris, 1870 (traduction » Alois Humbert), 
p- 281, 560. 
Agassiz, L. 
°72. New-York Weekly Tribune, Feb. 14, 1872. 
Crosse, H., et Fischer, P. 
°72. Journ. de conchyl., T. XX, p. 287 (nouvelles). 
Martens, E. von. 
°72. Lebende Pleurotomarien (Nachbl. der deutsch. Malak. Ges., T. IV, 
DS7 2: p. 55). 
Reeve. 
°74. Conch. Icon. Pleurotomaria, Fig 1-2. 
Crosse, H. 
°76. Journ. de conchyl., T. XXIV, p. 216 (nouvelles). 
Hilgendorf. 
°77. Sitzungsber. der Ges. Naturforsch. Freunde zu Berlin, 1877. Sitzung 
von 20 marz, p. 72-73. 
Schepman. 
‘79. Kine neue recente Pleurotomaria (Tijdschr. der Ned. Dierk. Vereen., 
Deel IV, 1879, p. 162-167). 
Crosse, H. 
89. Journ. de conchyl., T. XXVIII, 1880, p. 203-204 (nouvelles). 


Martens, E. von. 
80. Conchyl. Mith., Vol. I, p. 33, Pl. VIII, Cassel, 1880. 


Dall. ‘ 
’81. Bull. Mus. of Comp. Zool. at Harvard College, Vol. IX, 1884. 


Crosse, H. 
82. Les Pleurotomaires de l’époque actuelle (Journ. de conchyl., T. XXX, 
1882, p. 5-22, Pl. I, Fig. 1-2). 
Crosse, H. 


82°. Note additionnelle sur le Pleurotomaria Rumphii, Schepman (Journ. de 
conchyl., Vol. XXX, 1882, p. 183-184). 
Schepman. 
82. Conchyliologische Bijdragen (Tijdsch. d. Ned. Dierk. Vereen., Deel VI, 
1882, p. 20-23, Pl. II, Fig. 1-8). 


242 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Tryon, G. W. 
83. Structur. and System. Conchology, Vol. II, p. 318, Philadelphia, 1883. 
Fischer, P. 
85. Manuel de conchyliologie, p. 849-851, 1885. 
Woodward. 
’°85. Onrecent and fossil Pleurotomariide (Geological Magazine, October, 
1885, p. 433-439, Pl. XI. Fig. 1). 


’°86. Journ. de conchyl., T. XXXIV. p. 106, 1886 (bibliographie). 


Sowerby. 
?87. Thesaurus Conchyliorum, T. V, 1887, p. 185, T. CDXC, Fig. 1-2. 


Agassiz, Alexander. 
°88. Three Cruises of the Blake, Vol. II. (Bull. of the Mus. of Comp. Zodl. 
at Harvard College in Cambridge, Vol. XV. p. 69; Fig. 288 et 289). 


Shaler and Foerste. 
°88. Preliminary Description of North Attleborough Fossils (Bull. of the 
Mus. of Comp. Zodl., Vol. XVI. p. 30-31, Pl. II. Fig. 11). 
Dall. ; 
’89. Explorations of United States Coast Survey Steamer “ Blake.” Report 
on the Mollusca, Part II. Gastropoda and Scaphopoda (Bull. of the Mus. 
of Comp. Zool. at Harvard College, Vol. XVIII. 1889, p. 396-403, 
Pl. XXIX., XXX., XXXI., XXXIJ. (partim).) 
Lechmere Guppy. 
°90. On a Specimen of Pleurotomaria from Tobago, Trinité, 1890, broch. 
in-8° de 2 pages. 
Pilsbry, A. 
90. Manual of Conchology, Structural and Systematic, Vol. XII. 1890, 
p- 99-72, Pl. LVI.-LVII. 
Crosse, H. 
91. Journ. de conchyl., T. XX XIX. 1891, p. 68, p. 360 (nouvelles). 
Damon. 
°91.—The Conchologist, Vol. I. 1891, une planche hors texte. 
Lechmere Guppy. , 
91. Ona specimen of Pleurotomaria from Tobago (Proc. Zod]. Soc. London, 
1891, p. 484-485). 
Pilsbry, 
‘92. The Nautilus, Vol. V. 1892, p. 119 (General Notes). 
Collinge, W. E. 
94. The Journal of Malacology, Vol. IIL. 1894 (notes), p. 20. 


Cooke, A. H. 
95. The Cambridge Natural History, Molluses, London, 1895. 
Pilsbry. 


"95. Nautilus, Vol. VIII. 1895, p. 131 (notes). 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 243 


Vincent, E. 
°96. Note préliminaire sur le Pleurotomaria (Soc. roy. Malac. de Belgique, 
proces verbal de la séance du 12 décembre 1896, Pl. LX XVII, Fig. 1). 
Mitsukuri. 
96. A living Specimen of Pleurotomaria Beyrichii (Annotationes zoologice 
japonenses, Vol. I. Tokyo, 1897, p. 67). 
Sacco. 
°97. I Molluschi dei terreni terziarii del Piemonte e della Liguria, Parte 
XXII. 1897, p. 2. 
Bouvier, E.-L., et Fischer, H. 
°97. Sur Porganisation et les affinités des Pleurotomaires (Comptes rendus de 
l’Académie des sciences, mars 1897). 
Bouvier, E.-L., et Fischer, H. 
’98. Sur l’organisation des Pleurotomaires (Comptes rendus de |’ Académie 
des sciences, mai 1898). 


2° PaRTIE GENERALE (ANATOMIQUE). 


Lacaze-Duthiers, H. de. 
59. Mémoire sur le systeme nerveux de |’Haliotide (Annales des sciences 
naturelles, Zoologie, 4° sér., T. XII, 1859). 
Walter, G. 
°63. Mikrosocopische Studien ititber das Central-nervensystem wirbelloser 
Thiere, Bonn, 1863. 
Lacaze-Duthiers, H. de. 
°72. Otocystes ou capsules auditives des Mollusques (Gastéropodes) [ Archives 
de zoologie expérimentale, 1'¢ sér., T. I, 1872]. 
Ihering, H. von. 
°77. +Vergleichende Anatomie des Nervensystems und Phylogenie der Mol- 
lusken, Leipzig, 1877. 
Spengel. 
*81. Die Geruchsorgane und das Nervensystem der Mollusken (Zeitschr. wiss. 
Zool., Bd. XXXV, 1881). 
Hubrecht, A, 
81. Proneomenia Sluiteri (Niederl. Arch. Zool., Suppl. I, 1881). 
Béla Haller. 
*82. Die Organisation der Chitonen der Adria (Arbeit. Zool. Institut Wien, 
T. IV, 1882). 
Hubrecht. 
83. Contribution a la morphologie des Amphineures (Bull. scient. du Nord 
et de la Belgique, 5° année, 1882). 
Béla Haller. 
*84. Untersuchungen iiber marine Rhipidoglossen. Erste Studie (Morpholog- 
Jahrbuch, Bd. IX, 1884). 


244 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Wegmann. 

84. Contribution 4 l’histoire naturelle des Haliotides (Archives de zoologie 

expérimentale, 2° sér., T. II, 1854). 
Boutan, L. 

°86. Recherches sur l’anatomie et le développement de la Fissurelle (Archives 

de zoologie expérimentale, 2° sér., T. III bis, 1886). 
Bouvier, E.-L. 

°86. Contribution A |’étude des Prosobranches pténoglosses (Bull. Soe. 

malacol. de France, 1886). 
Béla Haller. 

°86. Untersuchungen iiber marine Rhipidoglossen. IT. Textur des Central- 

nervensystems und seiner Hiillen (Morphol. Jahrb., Bd. XI, 1886). 
Bouvier, E.-L. 

87. Systeme nerveux, morphologie générale et classification des Gastéropodes 
prosobranches (Annales des sciences naturelles, Zoologie, 7¢ sér., T. III, 
1887). 

Biitschli, O. 

’°87. Bemerkungen tber die wahrscheinliche Herleitung der Asymmetrie der 
Gastropoden, spec. der Asymmetrie im Nervensystem der Prosobranchiaten 
(Morph. Jahrbuch, Bd. XII, 1887). 

Garnault, P. 

°87. Recherches anatomiques et histologiques sur le Cyclostoma elegans, Bor- 

deaux, 1887. 
Pelseneer, P. 

87. Sur la valeur morphologique de ]’épipodium. des Gastropodes rhipido- 
glosses (Comptes rendus de |’Académie des sciences, T. CV, n° 14, 1887, 
et Bull. scient. de la France et de la Belgique, 1887). 

Boutan, L. 

*88. Contribution a l’étude de la masse nerveuse ventrale (cordons palléaux- 
_viseéraux) et de la collerette de la Fissurelle (Archives de zoologie expéri- 
mentale, 2° sér., T. VI, 1888). 

Pelseneer, P. 

88. Sur l’épipodium des Mollusques (Bulletin scientifique de la France et de 

la Belgique, 3° sér., 17* année, 1888). 
Béla Haller. 

89. Réplique A M. Boutan (Sur |’épipodium des Mollusques) [Bulletin 

scientifique de la France et de la Belgique, 3° sér., T. I, 1889). 
Lacaze-Duthiers, H. de. 

90. De la valeur relative de quelques procédés d’investigation en anatomie 

-comparée (Archives de zoologie expérimentale, 2° sér., T. VILI, 1890). 
Pelseneer, P. 

90. Sur l’épipodium des Mollusques (deuxiéme note) [Bulletin scientifique 

de la France et de la Belgique, T. XXII, 1890]. 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 245 


Thiele, J. 
"90. Ueber Sinnesorgane der Seitenlinie und das Nervensystem der Mollusken 
(Zeits. wiss. Zool., Bd. XLIX, 1890). 


Boutan, L. 
~ 90. Le systéme nerveux du Paramophorus (Scutus) dans ses rapports avec 
Je manteau, la collerette (manteau inférieur) et le pied (Revue biologique 


du Nord, T. II, 1890). 


Pelseneer, P. 
91. Sur l’épipodium des Mollusques (troisitme note) [Bulletin scientifique 
de la France et de la Belgique, T. XXIII, 1891}. 


Bouvier, E.-L. 

*92. Observations sur les Gastéropodes opisthobranches de la famille des 

Actéonidés (Comptes rendus de la Société philomathique de Paris, 24 
décembre 1892). 


Thiele, J. 
"92. Beitrage zur Kenntniss der Mollusken, I. Ueber das Epipodium (Zeits. 
wiss. Zool. Bd. LIII, 1892). 


Bouvier, E.-L. 
‘93. Sur la distorsion des Gastéropodes hermaphrodites (Comptes rendus de 
la Société philomathique de Paris, 14 janvier 1893). 


Grobben, K. 
94, Zur Kenntniss der Morphologie, der Verwandtschaftsverhaltnisse und des 
Systems der Mollusken (Sitz. Ber. Akad. Wien, Bd. CIIL, p. 61-86). 


Béla Haller. 

94. Studien tiber Docoglosse und Rhipidoglosse Prosobranchier, nebst 
Bemerkungen tiber die phyletischen Beziehungen der Mollusken un- 
teremander, Leipzig, 1894. 

Béla Haller. 

94". Beitrage zur Kenntniss der Placophoren (Morphol. Jahrb., Bd. XXT, 

1894). 
Nabias, B. de. 

’94. Recherches histologiques et organologiques sur les centres nerveux des 

Gastéropodes, Bordeaux, 1894. 
Pelseneer, P. 
94. Recherches sur divers Opisthobranches (Mém. Cour. des savants 
étrangers. Académie de Bruxelles, T. LIII, 1894). 
Pelseneer, P. 
94° Introduction a l'étude des Mollusques, Bruxelles, 1894. 
Plate, L. 


"95. Bemerkungen tiber die Phylogenie und die Entstehung der Asymmetrie 
der Mollusken (Zoolog. Jahrb., Bd. IX, 1895). 


246 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Plate, L. 
°95*. Ueber den Bau des Chiton aculeatus (Sitz. Ber. Ges. Naturf. Freunde, 
Berlin, 1895, p. 154-164). 
Thiele, J. 
°95. Ueber die Verwandtschaftsbeziehungen der Amphineuren (Biol. Central- 
blatt, Bd. XV, 1895). 


Plate, L. 
’96. Ueber einige Organisationsverhaltnisse der Chitonen (Sitz. Ber. Ges. 
Naturf. Freunde, Berlin, 1896, p. 42-50). 
Plate L. 
°96*. Ueber die Organisation einiger Chitonen (Verhandl. deutsch. Zool. 
Gesellsch., 6¢ Jahresversammlung, 1896). 
Bouvier, E.-L., et Fischer, H. 
°96. Sur l’organisation et les affinités des Pleurotomaires (Comptes rendus de 
l Académie des sciences, mars 1897). 
Thiele, J. 
97. LBeitrage zur Kenntniss der Mollusken. Ueber Hautdriisen und Derivate 
(Zeits. wiss. Zool., 1897). 


Boutan, L. 
°98. L/organe glandulaire périphérique de |’Helcion pellucidum Lin. (Archives 
de zoologie expérimentale, 3° sér., Vol. V, 1898). 
Bouvier, E.-L., et Fischer, H. 
°98. Sur l’organisation des Pleurotomaires (Comptes rendus de lAcadémie 
des sciences, mai 1895). 


ss 


PLEUROTOMAIRES 


—— 


Bouvier del 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 247 


EXPLICATION DES PLANCHES. 


Lettres Communes. 


Organes divers. — Ao, aorte antérieure; F, pied; M, masse buccale; M', mufie; 
0, otocyste; @, wil; ¢, tentacule; U, manteau; V, muscle columellaire. 

Ganglions. — B, ganglions buccaux (stomato-gastrique) , C, ganglions cérébroides; 
I, saillie labiale; Cd, ganglion palléal droit ou corne palléale supérieure droite ; 
Cq, ganglion palléal gauche ou corne palléale supérieure gauche; (1, corne pal- 
léale unique des Pleurotomaires ; Ps, partie palléale des centres nerveux du pied; 
Pi, partie pédieuse des centres nerveux du pied; s, sillon palléo-pédieux. 

Commissures, connectifs, nerfs. —c, commissure cérébroide ; ¢1, commissure labiale ; 
h, branche sus-intestinale de la commissure viscérale; h1, branche sous-intesti- 
nale de la commissure viscérale; £, connectif cérébro-buccal ; £1, connectif céré- 
bro-pédieux ; £2, connectif cérébro-palléal ; 7, commissure palléo-pédieuse ; f, nerf 
optique; o’, nerf acoustique; m1, m2, m,....nerfs labiaux; s1, s*, s3.... nerfs 
buccaux; ¢’, nerf tentaculaire; p, nerfs pédieux; p’, nerfs pédieux antérieurs ; 
pu, nerfs mixtes (palléo-pedieux). 


PLANCHE I. 


Fig. 1. Exemplaire de Pleurotomaria Quoyana, tel qu’il nous a été communiqué, 
vu du coté gauche. S, sole pédieuse. 

Fig. Région céphalique du méme, ouverte sur la ligne médiane dorsale. 

Fig. 3. Cavité antérieure du corps du méme exemplaire ouverte sur la ligne mé- 
diane dorsale ; la masse buccale est enlevée. S, sole pédieuse; d, nerf 
issu de la branche sus-intestinale de la commissure viscérale. 

Fig. 4. Partie antérieure du cordon palléo-pédieux gauche, vue par sa face ex- 
terne. a, a!, a, nerfs issus de la partie palléale. 

Fig. 5. Partie antérieure du cordon palléo-pédieux droit du Turbo radiatus Gme- 
lin, face externe; a, grand nerf palléal droit; a1, a2, a3, autres nerfs 
issus de la partie palléale du cordon. 

Fig. 6 et 7. Branches gauche et droite du syst?me nerveux stomato-gastrique dans 
le Chrton fascicularis ; les cellules nerveuses se concentrent de chaque 
coté en deux ganglions. 


Se 


Fig. 


Fig. 


Fig. 


Fig. 


Fig. 
Fig. 


Fig. 
Fig. 
Fig. 


Fig. 
Fig. 


Fig. 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


Fig. 


10. 


11. 


12. 


13. 


BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


PLANCHE II. 


Méme préparation que celle de la Figure 3, mais le lobe antérieur du pied 
ayant été fendu et la cavité antérieure largement ouverte, on peut voir 
les parties nerveuses qui avoisinent le pied. v, trone vasculaire qui 
parait plonger dans le pieden s’y bifurquant; e, 6, ’, nerfs parictaux qui 
se détachent des connectifs cérébro-palléaux ; c et c’, nerfs pariétaux ou 
columellaires issus des connectifs cérébro-palléaux ; /, /’, nerfs columel- 
laires postérieurs ; d, nerf des parois dorsales. 

Méme préparation que la précédente, mais la sole pédieuse a été étalée et 
en partie disséquée du coté ventral pour mettre 2 découvert les cordons 
palléo-pédieux. Lettres accessoires comme pour la Figure 8. 

Ganglion cérébroide droit du Pleurotomaria Quoyana, vu par la face 
interne. 

Figure indiquant la disposition anatomique et les connexions des parties 
antérieures des cordons palléo-pédieux. La préparation est vue sous le 
méme aspect (face inférieure) que celle de la Figure 9, seulement les 
cordons ont été disposés de teile sorte que celui de gauche est vu par.sa 
face externe, tandis que celui de droite est vu par sa face externe en 
avant de la grosse commissure palléo-pédieuse 7, par sa face interne en 
arriere a, a}, a’2, nerfs émis par le ruban palléal du cordon gauche; 
a’, a’ 2, a’3, nerfs émis par le ruban palléal du cordon droit. Les autres 
lettres accessoires comme dans la Figure 8. 

Systtme stomato-gastrique du Pleurotomaria Quoyana. 

Partie antérieure des cordons palléo-pédieux de la Cemoria noachina, L., 
d’apres M. Béla Haller (94, Fig. 142). C”’, cornes inférieures ou palléo- 
pédieuses ; Cg, Cd, cornes supérieures purement palléales (ganglions 
palléaux gauche et droit). 


PLANCHE III. 


Une demi-rangée de gauche de la radule, vue par-dessous. X 50. 

Dent impaire et quarante-trois premiéres dents du cété gauche. X 650. 

Région antérieure d’une rangée; dent impaire, les trois premieres dents 
droites; les huit premieres dents gauches. 70. 

Dent impaire, vue de profil. La ligne d’insertion est a droite. X 70. 

Dent impaire, vue par dessous et un peu de trois quarts. > 70. 

Dent impaire montrant, vue de trois quarts, la surface antérieure pourvue 
de ses deux expansions foliacées. > 70. 

Premiére dent gauche, du cdté externe. x 70. 

Deuxieme dent gauche, du cété externe. > 70. 

Troisitme dent gauche, du cété interne. X 70. 

Les deux otocystes, avec l’origine des nerfs acoustiques. X 20. 

Groupe d’otolithes. > 500. 

Fragment de la radule, vu par dessous, limité & la longueur d’une rangée, 
montrant le mode d’insertion des dents. Sur les bords extrémes, les 
téguments ont été enlevés sans laisser apercevoir, dans leur partie libre, 
les dernitres dents flabelliformes. X 20. 

Une machoire. xX 8, 


Age.’ 
PLEUROTOMAIRES 


PLEUROTOMAIRES 


jie’ 


waiee* 


ll” Merce 


ie) 


Lartand #0 


HFischer ded , 


' = Ye 


PLEUROTOMAIRES 


Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 


— 


—_ — 
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— 
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SS SS 
ND OR 


SOHOMDIAMA WD we 


BOUVIER ET FISCHER: PLEUROTOMAIRES ACTUELS. 249 


PLANCHE IV. 


- Groupe des trois dents 28, 29 et 30, du cété gauche. 70. 


Vingt-huititme dent gauche. » 70. 
Vingt-neuvieme dent gauche. > 70. 


. Trentieme dent gauche. 70. 
. Groupe des huit derniéres dents (110-117) du cété gauche. X 70. 
. Trente et uniéme dent gauche. 70. 


Trente-troisiéme dent gauche. 70. 
Trente-septitme dent gauche. > 70. 


- Quarante-deuxieme dent gauche. X 70. 
. Extrémité supérieure de la cent neuvieme dent gauche. X 260. 


Quarante-cinquiéme dent gauche. X 70. 


- Quarante-huititme dent gauche. x 70. 

. Extrémité antérieure de la cinquantitme dent gauche.  X 140. 

. Extrémité antérieure de la soixante-sixitme dent gauche. Xx 140. 
- Soixante-sixiéme dent gauche. > 70. 


Cent troisitme dent gauche. X 70. 
Cent neuvieme dent gauche. x 70. 


BULLETIN 


MUSEUM OF COMPARATIVE ZOOLOGY 


AT 


HARVARD COLLEGE, IN CAMBRIDGE. 


VOL. XXXIII. 


CAMBRIDGE, MASS., U.S. A. 
1899. 


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Bulletin of the Museum of Comparative Zodlogy 
AT HARVARD COLLEGE, 
Vout. XXXII. 


THE ISLANDS AND CORAL REEFS OF FUL. 


By ALEXANDER AGASSIZ. 


WitH OnE HunDRED AND TWENTY PLATEs. 


CAMBRIDGE, MASS., U.S. A.: 
PRINTED FOR THE MUSEUM. 


May, 1899. 


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TABLE OF CONTENTS. 


INTRODUCTION . F £8 he, j : 
Some PoINTs IN THE Tamena sue ON Senne Reuss 
TRACK OF THE “YARALLA.” Plate 1 

Tue Peiacic Fauna or Fis1 Le 

CLASSIFICATION OF THE ISLANDS OF Fis1 . 

Votcanic IsLanps ; Riis: PRG RN Ae ae 
Koro. Plates 3°, 19°, Fig. g SPAN OME VE forens rr eeek 
Mbatiki. Plate 12 
Moala. Plates 16, 57. Rm a ee a 
Ngau. Plate 11°, Fig. 1-3; Plates 12, 13 RS or, 2 


Mambulitha Reef. Platel2.. SW age hear Pace han Fal the 
Nairai. Plate 11°, Fig. 4; Plates 12, 14, 58, 59 Br ci Se oe 
Wakaya. Plates 3*; 11°, Wigs: 7,8; Plates 15,55,56 . . . 
Makongai. Plate 11*, Fig. 9; Plate UTES RS PON Coa Ct eee 


Mbengha. Plates 8, 11°, Fig.5; Plates 46-49. 

Kandavu. Plates 10, 11, 50 

Great Astrolabe Reef. Plates ny Tees i He Figs: 10-13: Plates 51, 52 

North Astrolabe Reef. Plates 11, 11%, Fig. 14; Plates 53, 54 

Budd Reef. Plates 4, 18, 70 lanes Me ne 

Komo. Plate 19*, Figs. 9-11; Plates 22, 63-65 

Olorua. Plate 22 . 

Totoya. Plates 16, 19°, ee 4- 7; Plates 23, 66-69 . 

iaviuni: Plates4,18,60. .. . . ; Seis : 
IsLANDS COMPOSED OF Higa hieac Ghimateonnes es ee Plate 2 

Ngele Levu. Plates 17, 17*, Figs. 5-12; Plates 95-99 

Nuku Mbasanga. Plates 18, 22, Fig. 18; Plate 108 

Nukusemanu. Plates 18, 103-107 

Wailangilala. Plates 18,109,110 . 

Tuvutha. Plates 20, 88, 89 

Naiau. Plates 20, 22°, Fig. 1. 

Wate Vara. Plate 9. . ©. 2 

Yathata and Kaimbo. Plate 19 . 

Aiwa. Plates 21, 22%, Figs. 13-15 

Oneata. Plates 21, 22%, Figs. 10-12 

Namuka. Plate 22 


Yangasé. Plates 22, 22%, Fig 8, 9; Plates 90-938 .. 
Ongea. Plates 22, 99" A Bias 4 ie este od 5 aes 
Fulanga. Plates 22, 22%, Fi igs. 4,5; Plates 80-84 


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2 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Marambo. ‘Plate 22°52. 2.0 Me hea eed hat ea oe 
Wangava. Plate 22. sep Re ee ee tA in 3) Wak Dei) Pore ee ed 
Vatu Leile. Plates 9, 17° , Bigs: 1-45: Plates 100-102 ~. 5) 5 sees 
fine, Socks ob Rist ¢ ies eee. ae 
Tue TerRTIARY ELEVATED LIMESTONES OF FIJI... . cate 
ISLANDS PARTLY VOLCANIC, PARTLY COMPOSED OF Eevizes Linen 
Kimbombo. Plates 19, 61 . a Ree ere oo se 
Exploring Isles: Vanua Mbalavu. Plates 19, 19*, Figs. 1-3; Plates 72-77 
Mango. Plates 19, 22°, Fig. 3; Plates 85-87 
Lakemba. Plate 19. 
Thithia. Plate 20 
Naitamba. Plate 19. 
Mothe. Plate 22 oP ee ee 
Kambara. Plates 22, 22*, Fig. 2; Plates 78, 79 
Thikombiaira. Plate 17 
Sunpry ATOLLS ae y 
Pitman Reef. Plate 18. a 0 
Motua Levu and Motua lai lai. Plates 18, 112 
Williamson Reef. Plate 19 
Bell Reef. Plate 19. Bh isk ee SS oe 
Adolphus Reef. Plate 1S) eau tssew 21. 3) 0 een 
‘ova Reel.- Plate:23° ies geaeper ©. 4 ose Fe oe ce bay een 
Thakau Momo. Plates 12, 14, 23°, Fig. 6 
Thakau Lekaleka. Plates 21, 111 
LaGoons or ATOLLs. : 
Extinct CRATERS AND pee ; ER Py i 
Viti Levc Reers. Plates 1-3, 5-7, 20°, Figs 9- 12 ; Plates 24-27, 31-45 
Plateau off Nandi and Yasawa : 
Suva Reef Flats. Plates 5, 28-30, 65, 76 
IsLaNDS AND CorAL REEFS DESCRIBED FROM THE Sead 
Viti Levu and Vanua Levu. Plates 3, 3%, 4, 23 : 
Mbukata tanoa, or Argo Reefs. Plates 20, 20*, Figs. 5-8 ; ines 21 
Thikombia. Plate 17 
Onoilau. Plate 178, Figs. 13- 16; Plate 238, Figs. it gd 
GENERAL SKETCH OF THE Figt Istanps AND Corat Reers. Plate 1. 
List OF FIGURES IN THE TEXT 
EXPLANATION OF THE PLATES . 


PAGE 


The Fiji Islands and Coral Reefs. By ALEXANDER AGASSIZ. 


INTRODUCTION. 


On our arrival in Suva the first day of November, 1897, we found the 
*“ Yaralla,” a twin screw steamer of about five hundred tons, chartered 
from the Australasian United Steam Navigation Company, awaiting us. 
The boat proved admirably suited for our purpose, the managing agent 
of the company at Brisbane, Mr. Elliot Bland, aud Captain Downs, of 
Sydney, having spared no pains in fitting her out. 

Previous to our departure I shipped to Australia our outfit for 
dredging, sounding, and deep-sea towing, as well as all the materials 
necessary for preserving our collections. This equipment we found 
safely stored in the “ Yaralla.” Dr. W. McM. Woodworth and Dr. A. G. 
Mayer accompanied me as assistants. Dr. Woodworth and my son 
Maximilian have taken a large number of photographs illustrating the 
physiognomy of the islands and reefs. Dr. Woodworth devoted his 
time in part to the care of the Worms, and Dr. Mayer to the Acalephs 
of Fiji. 

I have to thank the State Department at Washington for their kind 
offices in obtaining for me letters from the British Foreign Office to 
the Government of Fiji. Sir George O’Brien, the High Commissioner 
of the Western Pacific, gave us all possible facilities for visiting the 
different islands of the group. I am also indebted to the Hon. J. 
Stewart, Colonial Secretary, and to the Hon. W. L. Allardyce, Assistant 
Native Commissioner, for assistance and advice. To Dr. Corney and 
the Hon. John Berry I owe information of value regarding the existence 
of elevated reefs at points I have not examined. To Captain Calder, the 
agent of the Australasian United Steam Navigation Company at Fiji, I 
am greatly indebted for his exertions on our behalf. Finally, Captain 
R. Cocks, our pilot, and Captain Thomson, as well as the officers and 
crew of the “ Yaralla,” were indefatigable in promoting our inter- 
ests. I have also to thank specially Sir William C. Van Horne and 
Mr. T. G. Shaughnessy, the President and Vice President of the Cana- 
dian Pacific Railway, for placing at our disposal a private car from 


4 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


Montreal to Vancouver, and for despatching to Fiji a number of cases 
which could not be shipped via Australia. I am also under great obli- 
gations to Admiral Sir W. J. L. Wharton, R. N., and to Captain W. U. 
Moore, R. N., for their unceasing interest and advice while planning my 
trip to Fiji. 

Thanks to the admirable charts of Fiji, which owe their origin to the 
surveys of the United States Exploring Expedition under Wilkes, and 
their elaboration in great detail by the subsequent British surveys of 
Captain Denham and Lieutenants Moore and Richards, it was possible 
to cover a great deal of ground by picking out from the charts the inter- 
esting and critical points for examination, and thus to make a very rapid 
yet fairly accurate survey of the coral reefs. The accuracy of the Ad- 
miralty Charts enabled us to enter safely into the lagoons, and to select 
our anchorages with confidence. The reproduction here of the Fiji 
charts, together with photographs of the most characteristic views, will 
better serve to give a faithful picture of the islands and reefs of Fiji 
than lengthy descriptions, and I hope in the discussion of the general 
_ questions to be able to illustrate my arguments either by references to 
the charts or to the photographs of a group of islands of which Dana 
says, “The facts from the Feejee Archipelago illustrate the subject 
well.”! The larger scale charts of the Admiralty, such as those of 
Kandavu (A. C. 167), of the south and east coasts of Viti Levu (A. C. 
167, 845, 905), of Vatu ira Channel (A. C. 379), of Makongai and 
Wakaya (A. C. 1250), of Suva (A. C. 1757), of Levuka Harbor (A. C. 
1244), of Ovalau (A. C. 1249), of such islands as Nairai (A. C. 741), of 
Moala (A. C. 1252), of Ngau (A. C. 1251), and of Totoya (A. C. 1248), 
contain an inexhaustible fund of information regarding coral reefs, and 
would serve as an invaluable basis for a minute zodlogical and geological 
survey of any island group such as I attempted for the Tortugas.? 


1 Dana, Corals and Coral Islands, p. 262. 
2 Mem. Am. Acad., Vol. XI. p. 107 (1883). 


CamBripGE, September 1, 1898. 


Nore. — Owing to my absence from Cambridge and to the delay in 
preparing the Plates for this volume its publication has been delayed 
until May, 1899. 


a ee EE oo <r 


or 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 


SOME POINTS IN THE LITERATURE ON CORAL REEFS. 


It will prevent considerable confusion if, before proceeding with the 
account of our expedition to Fiji, I should devote a few pages to the 
examination of some of the literature on coral reefs, in the light of 
the observations we made while at Fiji. 

On looking over the literature on coral reefs, one cannot fail to be 
struck with the amount of irrelevant matter which has been passed 
down from writer to writer. Statements made on hearsay have gradu- 
ally become facts. The observations of inexperienced persons receive 
general recognition. Special cases are discussed without reference to 
their limited or exceptional application. The whole question is often 
threshed out de novo, so that it is difficult to separate the new from the 
old. And, finally, information gathered from charts is substituted for 
observation in dealing with questions which the latter alone can settle. 
Every new investigator naturally adds important information from the 
field he surveys, and each has in his way described the numerous and 
varying conditions affecting the growth and existence of coral reefs in 
the tropical waters of the Atlantic and the Pacific. Recent explorations 
have only increased the number of questions to be solved regarding 
coral reefs ; and until the whole field has been examined in the light of 
these questions, it is hopeless to attempt a general revision of the 
theories regarding the formation of coral reefs. A revision based upon 
a partial examination, though it be more extensive than that of our 
predecessors, is usually brushed aside with the statement that even if 
the exception described is true, the old theory may yet be true in some 
other atoll region. Of course, such criticism can never end, and we may 
go on searching forever for this imaginary atoll, or until the last remain- 
ing atoll has been hunted down. 

In many quarters it has become a question of creed to uphold the 
Darwinian theory of subsidence as essential to the formation of atolls 
and of barrier reefs. Facts and arguments supporting other explana- 
tions are ignored or explained away in the most extraordinary manner. 
Regions which are cited by Darwin and Dana as typical become excep- 
tions when shown to be no longer characteristic regions of subsidence. 
Typical barrier reefs become patch reefs, atolls are dubbed pseudo 
atolls; so that the regions where true barrier reefs or typical atolls, 
which owe their origin to subsidence, can be examined, are little by little 
becoming very restricted. In fact, if we are to judge of the regions not 
yet examined, and which have not been examined by Darwin and Dana, 


6 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


there remain as extensive regions of possible subsidence only such isl- 
ands as the Marshall and Carolines, some of the atolls of the Gilbert and 
Ellice groups, and of the Paumotus. Yet, judging by analogy of the ad- 
joining districts of Fiji and Tonga, and of the descriptions given by Dana 
of the Paumotus, and by what we may gather from the charts in the 
light of our own exploration, it would not be launching a very doubtful 
proposition to assert that even in these island groups we shall find that 
the explanations we have given of the formation of atolls and of barrier 
reefs applies equally well to them. This still leaves the field open for 
observations in some of the coral regions of the Indian Ocean, and of 
the East Indian Archipelago. But in the districts which have been 
described as typical by both Darwin and Dana, recent observations have 
shown that other and more natural explanations than the theory of 
subsidence are sufficient to account for the formation of atolls and of 
barrier reefs. 

As is well known, Darwin’s experience among coral reefs was limited 
to a part of Tahiti, to.the west side of Mauritius, and to the Keeling 
Atoll. Though he passed through the Paumotus without examining 


any of the islands ; ? 


according to the narrative of the ‘‘ Beagle,” Darwin 
saw in the distance Hondeyw Island, passed by Taiaro along the shore of 
Kauehi and sailed between Elizabeth Island and Fakarava (Wittgen- 
stein) to Otaheite. Captain Fitzroy also sailed through the Navigator, 
Friendly, and Fiji Islands without anchoring anywhere. Dana? worked 
among the reefs at Tahiti, Samoa, aud the Feejees, though he did not 
visit the Eastern Archipelago, limiting his observations to the larger 
islands, Viti and Vanua Levu and Ovalau. He “twice visited the 
Hawaian Islands, landed and gathered facts from fifteen coral islands, 


some of them in the Paumotu Archipelago ;* one, Tongatabu, in the 


1 Narrative of the Surveying Voyages of his Majesty’s Ships Adventure and 
Beagle (1826-1836), Vol. III. p. 589. London, 18389. 

2 In “ Nature” (September 17, 1874, p. 408), Dana reviews a new edition of 
Darwin’s Coral Reefs suggesting that he had not given sufficient weight to the 
effects of temperature in limiting the distribution of coral reefs, and differing widely 
from Darwin as to the limits of the area of elevation and of subsidence in the 
Pacific. But in spite of minor differences he speaks of the “array of facts of his 
own (Darwin’s) observations, which illustrate the growth of coral formation” ; and 
subsequently, in 1885, when reviewing the whole subject again, Dana says in the 
American Journal of Science, Vol. XXX., August-September, 1885, p. 90: “The 
evidence which had satisfied him (Darwin) was satisfactory to me when I first 


learned of his views in Australia (in 1839), .. . and more decidedly later when I 
had been among the Friendly, Feejee, and other Pacific Islands.” : 
8 Honden, Dean, Aratica, Ahii, Raraka, Manhii, Kawehe, Metia, Clermont 


Tonnerre, and others examined by other members of the Exploring Expedition. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 7 


Friendly group; two, Taputeaua and Apia, in the Gilbert group, and 
five others near the equator, east of the Gilbert group: Swain’s, Fakaofu, 
_Oatafu, Hull and Enderbury Island, as well as the reef region of the 
Sooloo Sea and of the Straits of Malacca.” 

In my account of the coral reefs of the Sandwich Islands,’ I have 
given a short résumé of the results of the principal investigations on 
coral reefs since the days of Darwin and Dana down to 1889. What 
has been done since that time will be found referred to in Bouney’s 
edition of Darwin’s Coral Reefs,? in Kent’s “Great Barrier Reef,” in 
Langenbeck’s sketches? of recent work on the subject, as well as in the 
reports of the explorations I have carried on in the Bahamas and Cuba,* 
the West Indies,> Florida,® and the Bermudas’ in the Atlantic, and of 
the expeditions I have made to the Galapagos,® the Great Barrier Reef 
of Australia,® and Fiji.! 


1 Bull. Mus. Comp. Zoél., Vol. XVII. p. 121 (1889). 

2 Professor Bonney (Coral Reefs, Darwin, 1889, 3d ed., Appendix II. p. 290), 
has evidently confounded the views of Professor L. Agassiz on the extent of 
the formation of the southern extremity of Florida by coral reefs, dating back 
to 1854, with those which I have published in 1877, in 1880, in 1888, and again 
in 1896. Neither Dall nor Heilprin has examined the Florida reefs; their 
studies have been devoted to other parts of the peninsula, and did not extend 
south of the northern limit of the Everglades. Their criticisms in both cases 
apply to the views of Professor L. Agassiz, as my observations were limited 
to the reef region, and did not encroach on the area examined by Dall or Heilprin. 
But I have plainly shown by the borings at Key West that the recent coral forma- 
tion is of moderate thickness, not more than about fifty feet, and thatit is underlaid 
by a substratum of tertiary limestones, occasionally coralliferous, of a thickness of 
nearly two thousand feet. The area probably covered by the coral reef of Florida 
at the time of its greatest expansion is approximately shown on Plate XVII., Bull. 
Mus. Comp. Zo6l., Vol. XXVIII. No. 2,1896. I never made the statement quoted 
by Bonney that the recent coral reefs extended over any part of Florida north of the 
Everglades. On the contrary, I said in the conclusion of my memoir on the 
Tortugas and Florida Reefs (Mem. Am. Acad., Vol. XI. p. 116, 1883), “ All this 
evidence tends to show that the coral reefs had little, if anything, to do with the 
building up of the peninsula of Florida, north of Cape Florida.” 

8 R. Langenbeck, Die neueren Forschungen iiber die Korallenriffe, Hettner, 
Geog. Zeits., Bd. III., 1897, pp. 514, 566, 634. 

4 Bull. Mus. Comp. Zodl., Vol. XX VI. No. 1, 1894. 

5 Three Cruises of the Blake, 1888, Vol. I. p. 66. 

6 Bull. Mus. Comp. Zodl., Vol. XXVIII. No. 2, 1896. 

7 Tbid., Vol. XX VI. No. 2, 1895. 

8 Ibid., Vol. XXIII. No. 1, 1892. 

9 Ibid., Vol. XXVIII. No. 4, 1898. 

10 Am. Journ. of Science, February, 1898, Vol. V. p. 118. 


8 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


An excellent account of the Samoan Reefs has been published by Dr. 
Kriimer,! supplementing the earlier short notice of Dr. Graeff* on the 
reefs of the group; also interesting notes by Admiral Wharton,® on Sub- 
marine Banks of the Pacific. A careful account of the geology of the 
Friendly Islands by Lister,* published in 1891, seems to have escaped 
the attention of writers on coral reefs. A few notes on the reefs of some 
of the islands of the Bismarck Archipelago have been published by Dr. 
Dahl,® but the evidence he gives does not seem to me to warrant his 
conclusions. The great thickness of elevated reef he found (570 m.) 
may (as is the case elsewhere in the Pacific) not belong to the present 
epoch, as he takes it for granted, and no one supposes that elevation has 
necessarily always taken place uniformly either in time .or space over 
any great stretch of territory. 

The articles by Heilprin ® and by Ortman”™ on what they call “ Patch 
Reefs,” do not seem to me to have any special bearing on the general 
theory of coral reefs. The existence of such “patches” has long been 
known and referred to by Darwin, and by many writers on coral reefs, 
as reef patches. These patches occur in localities where fringing reefs for 
local causes would not flourish except at a little distance from shore and 
play a very subordinate part in the physiognomy of the coast. I am ata 
loss to understand the statements of Ortman regarding the reefs of 
Kaneohe Bay on the north shore of Oahu. The accurate observations of 
Hartt ® and of Rathbun on the moderate thickness of coral reefs off the 
coast of Brazil seem to have escaped Heilprin and Ortman, as well as other 
writers on coral reefs. Rathbun® has described the reefs along the 
Brazilian shore, and finds them all as “having very little height, but 
from the surface looking like massive structures.” Hartt *° and Rathbun 
have described the formation of extensive coral patches and the mode of 


1 Ueber den Bau d. Korallenriffe, Kiel, 1897. 

2 Samoa, Journal d. Museum Godeffroy, Vol. I. 

8 Foundations of Coral Atolls, Nature, February 25, 1897, p. 390. 

4 On the Geology of the Tonga Islands, Quart. Jour. Geol. Soc. London, No. 188, 
1891, p. 890. ; 

5 Zool. Jahrbiicher, Bd. XI. p. 141. 

6 Proc. Acad. N. S. Phila., 1890, p. 3138. 

? Zool. Jahrb., Bd. VI. p. 682. 

8 Hartt, in Chapter IV. p. 174, of the Geol. and Phys. Geog. of Brazil, 1870, 
describes the islands and coral reefs of the Abrolhos and the Recife de Lixo, 
where exist the “ chapeirdes,” as rising straight up from the bottom from a depth of 
forty to fifty feet. 

9 American Naturalist, Vol. XIII, June and September, 1879, Nos. 6 and 9. 

10 Geology and Physical Geography of Brazil, Boston, 1870. 


i i in . 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 9 


building up columnar masses which may eventually reach the surface 
forming mushroom- or even bell-shaped structures, of which enlarging 
rims may meet, “resulting in the formation of a connected reef surface 
supported by many upright pillars underneath from forty to fifty feet 
high,” the so called ‘“ chapeiroes” of the Portuguese. These patches fre- 
quently occur near the shore along the margin of a fringing reef, but are 
best developed in the deeper water of the Abrolhos regions and between 
these and the city of Bahia, growing upon the submerged rocky ledge. 
The number of reef building corals in Brazil is quite small, and Nulli- 
pores seem according to Rathbun to play a very important part in the 
building up of the limestone reefs. 

Professor Bonney? summarizes the position of the theory of coral reefs 
as now left (1889) in the following terms: ‘‘ That this theory may have 
been expressed in terms a little too comprehensive, that there may be a 
larger number of exceptional cases than was at first supposed, is quite 
possible. . . . It may very possibly be found that, as remarked by 
Mr. Bourne, the history of coral reefs is more varied and complicated 
than was at first supposed, but it seems to me that, as the evidence at 
present stands, it is insufficient to justify a decision adverse to Mr. Dar- 
win’s theory as a general explanation.” 

Professor Bonney, in spite of his intention to present an absolutely 
unbiassed expression, has, in common with most geologists not familiar 
with coral reefs, retained the view of the correctness of Darwin’s theory.” 
It can scarcely be said that the earlier examinations of coral reefs were 
made with the detail which has characterized the later explorations. 
The original work of Darwin was limited to a narrow field, and sup- 
plemented by data derived from charts and descriptions. Its correct- 
ness depends wholly upon the existence of masses of coral reefs of great 
thickness, where coral reefs exist as barrier reefs or atolls, and having 
assumed this the rest naturally followed. For no one will deny that sub- 
sidence is one of the possible modes of formation of masses of limestone 
of great thickness. But subsequent observers showed most distinctly 
that both atolls and barrier reefs occurred in regions of elevation. These 
exceptions are not limited to a single area. They occur in regions of 
the globe widely separated. While it undoubtedly is true, as remarked 


1 Loc. cit., p. 832. 

2 Dana’s support of Darwin’s theory, based as it was upon very great ex- 
perience among coral reefs, has probably been the principal cause of the gen- 
eral acceptance of the theory in late years, in spite of the attacks of recent 
investigators. 


10 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


by Professor Bonney,’ that Darwin has noticed most of the causes on 
which stress is laid by his critics, it should also be remembered that 
Darwin did not observe the phenomena subsequently examined, but 
merely suggested them as possibilities, and his critics may be excused 
for giving their observations a relatively greater value than to his 
theoretical views. 

The whole argument of the great thickness of coral reefs based upon 
the analogy of the so called raised reefs of Cuba, described by Prof. 
Crosby and myself, or of the fossil reefs, is of little value, as it has been 
pretty conclusively shown that these elevated reefs, not only in Cuba 
but in the Pacific, are beds of tertiary limestone intercalated with beds 
of moderate thickness in which corals are found, and the same is true of 
older fossil reefs. Furthermore, these huge masses of tertiary limestone 
which form the substratum upon which both in Cuba and in the Pacific 
recent corals have found a footing, have played no part in the shaping 
of the barrier or encircling reefs, or atolls, which, as we have attempted 
to show, owe their origin in the main to mechanical causes. 

Professor Bonney states that “ Much stress is laid upon the fact that 
many coral islands afford evidences of a certain amount of upheaval; this 
amount, in most cases, is but slight, and its significance appears to me to 
have been exaggerated” ; and he considers these indications to prove only 
oscillation. As far as the Fijis are concerned, the elevation extended 
over the whole group, and: has been shown to amount to more than 
a thousand feet. In Australia it extended along the whole east coast of 
Queensland for more than a thousand miles, and was more than twenty- 
five hundred feet in height! He further says, “If the coral reef be only 
a sort of cap concealing a hill of pre-existent rock, we may reasonably 
be surprised that the ‘ashlar rock’ of coral limestone has in no case 
so far yielded to the action of the atmospheric agencies as to lay bare its 
inner support.” We can answer this point most decidedly. In Florida 
the substratum underlying the recent coral reefs crops out at many 
places, and the highest points of some of the Keys consist of it. So do 
some of the hummocks in the southern part of the Everglades near Key 
Biscayne. In the Bermndas the greater part of the land of that group 
consists of the solian rocks which underlie the recent coral reef. In 
the Bahamas the same is the case, and along the northern coast of Cuba 
the tertiary limestone forming the substratum of the recent reefs crops 
out in all directions, while in Australia rocks underlying the Great Barrier 


1 Loe. cil., p- 824. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. ci! 


Reef can be traced as islands, islets, or negro-heads all along its line 
for more than a thousand miles. Finally, in the description of the 
islands of Fiji this substratum appears over and over again, either 
composed of volcanic rocks, or of great tertiary limestone banks. No 
better example can be found of the appearance of the substratum of 
the recent reefs than in Kaneohe Bay, Oahu, at the Sandwich Islands, 
where the reef is studded with islets and negro-heads consisting of 
voleanic rocks. 

That corals grow in lagoons is well ascertained, and nowhere is it 
better seen than in Fiji, where nearly all the islands enclosed by barrier 
reefs are edged with fringing coral reefs. But why that should prevent 
a lagoon from being formed I cannot see. A lagoon is not bounded 
by a reef forming a closed wall rising well above the level of the sea. 
The greater part of the reef of many a lagoon of an atoll or barrier reef 
has from two to three fathoms of water upon it at high tide. The reef is 
also riddled on all sides with narrow channels or openings with from one 
to two fathoms or more at low tide, in addition to the wider and deeper 
passages to leeward, through which access is gained into the lagoon. 
But for all this the lagoon exists, while it may not have more than a 
few fathoms in maximum depth. This, however, does not prevent the 
coral heads on the inner slope of the reef from gradually becoming con- 
nected with the reef, and from encroaching little by little, but very 
slowly, upon the outer margin of the lagoon to a depth of seven or eight 
fathoms, at which the growth is checked either from the sediment accu- 
mulating on the floor, or from the strength of the currents scouring the 
bottom of the lagoon. The amount of dead coral which is ground up 
upon a reef flat is considerable. Much of it is cemented together and 
forms a breccia in the cavities of the coral heads, or in the open spaces 
between them. Still more of it is changed into sand and mud, which 
cover the floor of the lagoons of barrier reefs and of atolls, and finally 
a quantity is carried off in solution after the dead coral has become 
thoroughly rotten and crumbling. 

Darwin also visited the western side of Mauritius, where, he says:} “It 
is probable that a reef on a shelving shore, like that of Mauritius, would 
at first grow up not attached to the actual beach, but at some little 
distance from it; and the corals on the outer margin would be the 
most vigorous. A shallow channel would thus be formed within the 
reef; and this channel could be filled up only very slowly with sediment, 


1 Darwin’s Coral Reefs, 3d ed., 1889, p. 72. 


12 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


for the breakers cannot cut on the shores of the island,’ and they do not 
often tear up and cast inside fragments from the outer edge of the reef, 
while every streamlet carries away its mud through breaches in the 
reef... . A fringing reef, if elevated in a perfect condition above the 
level of the sea, would present the singular appearance of a broad dry 
moat bounded by a low wall or mound.” 

Darwin, when meeting Semper’s objection that the existence of atolls 
or barrier reefs in a region of elevation was a fatal argument against 
his (Darwin’s) views, is obliged to say that therein “seems to me no 
improbability in their having originally subsided, then having been up- 
raised . . . and again having subsided.”? He further says, “ The exist- 
ence of atolls and of barrier reefs in close proximity is manifestly not 
opposed to my views.” Certainly not, but their existence in an area of 
elevation as claimed by Semper is. Darwin also says that, ‘‘ When the 
land is prolonged beneath the sea in an extremely steep slope, reefs 
formed there during subsidence will remain closely attached to the 
shore, and will be undistinguishable from fringing reefs.”* This seems 
to me impossible. The disintegration of the inner edge of the fringing 
reef, the action of the sea upon this disintegrated material, the solvent 
action of sea water, all will tend to form a channel between the outer 
parts of the reef and the shore, as is evidently the case in almost all 
fringing reefs, which show either an incipient channel where boats may 
circulate at high water, or a belt of considerable width in which the coral 
fringing the land has been killed by the silt brought down from the ad- 
jacent slopes, and has been decomposed, and, crumbling to sand or mud, 
is gradually being carried off at each high tide, forming a channel which 
when wide enough and deep enough becomes sufticiently prominent to 
change the fringing reef into a barrier reef. 

The difficulties encofntered in attempting to meet the many sugges- 
tions made by Darwin regarding reefs which he did not examine are 
well exemplified in the account which he gives of Rose Island, one of 
the Samoa group. 


1 This Yould depend upon the width and slope of the fringing reef. Many of 
the narrow fringing reefs in Fiji have a uniform slope towards the lagoon, and do 
not present the structure described by Darwin. 

2 Darwin’s Coral Reefs, 3d ed., p. 228. 

8 Ibid., p. 229. 

4 Tbid., p. 212: “The lagoon is very shallow, and is strewn with numerous large 
boulders of voleanic rock.” (Negro-heads, A. Ag.) He further says: “ This island, 
therefore, probably consists of a bank of rock, a few feet submerged, with the 
outer margin fringed with reefs. Hence it cannot be properly classed with atolls, 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 13 


Bonney? similarly takes Dana’s account of the eastern half of the 
Fiji Archipelago, as if it were based upon actual observations. Dana 
did not visit that part of Fiji, but derived his information from the sur- 
veys of these islands made by the officers of the United States Exploring 
Expedition. His statements are derived from the charts. 


TRACK OF THE “ YARALLA.” 


The track which we followed (Plate 1) was so arranged as to include 
for our first trip one or two of each type of island, and of the different 
types of atolls and barrier and fringing reefs in the group. Starting from 
Suva the day after our arrival, we visited Mbengha, returned to Suva, and 
went in the following order to Ovalau, Wakaya, Makongai, and Koro, 
skirted along the western shores of Taviuni, examined the northeastern 
coast of the same island, passed out through the Matangi Passage to 
Motua Levu and Motua lai lai, and skirted along the western extremity 
of the Nanuku reefs. From there we steamed to Wailangilala, where 
we landed our boring apparatus and the crew of whites and of natives 
needed for working the same. We then'turned north, passing close to 
Nuku Mbasanga and Adolphus Reef, and entered Ngele Levu Lagoon. 
We next examined the Ringgold Islands, paying special attentioy to 
Thombia in Budd Reef. From there we returned to a former anchorage 
off Thurston Point on Taviuni, and followed much the same track back 
to Wailangilala, where we found our boring party settled and at work. 
We then steamed south; examining Williamson Reef, the Kimbombo 
islets, Bell Reef, and entered the Vanua Mbalavu Lagoon through the 
Ngillangillah Passage. Passing out of the lagoon by the Tonga Pass, 
we touched at Mango, Tuvutha, Naiau, and Lakemba. We steamed past 
Aiwa, entered the Oneata Lagoon, visited Thakau Lekaleka, touched at 
Mothe, entered the Komo Lagoon, the Yangas& Cluster, and the Ongea 
Lagoon. We passed by Fulanga close to the entrance, which was too 


in which, as we have reason to believe, the foundations always lie at a greater 
depth [The Italics are mine. — A. Ac.] than that at which the reef constructing 
polyps can live.’ Yet Dana and Wharton, as well as Kriimer, say that it is an 
atoll, and the charts show it to be an atoll fully as much as any similar island 
in Fiji. So that if the islands in Fiji which resemble it, and which according to 
Dana and my own observations are atolls, yet according to Darwin they would 
not be so regarded, we shall have to seek for an atoll answering his requirements 
outside of the Fiji group. 
1 Loc. cit., p. 310. 


14 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


shallow to allow our vessel to enter, but near enough to get an excellent 
idea of its characteristic structure. We next touched at Kambara, an- 
chored in the crater of Totoya, made for Moala, and thence for Solo 
Lighthouse, examined the North Astrolabe Reef, steamed through the 
Great Astrolabe Reef, coming out west of Ono, examined a part of the 
northern shore of Kandavu, and then made for Vatu Leile, returning to 
Suva. On our second trip we visited Ngau, Nairai, the Horseshoe Reef, 
Mbatiki, and, entering the Moturiki Channel south of Ovalau, examined 
the inner side of the barrier reef as far as Mbau, and explored the bar- 
rier reef from Moturiki to Suva. During our third trip we steamed 
along the southern coast of Viti Levu, going as far west as Nandronga. 
Skirting the reef as closely as was prudent, we were able to follow the 
changes of the great barrier reef of Viti Levu west of Suva as it grad- 
ually passes into a fringing reef and disappears off the Singatoka River, 
to reappear again, first as a fringing reef, next as a barrier reef extending 
beyond the Nandi waters to the west of Nandronga. We then paid 
a second visit to Vatu Leile, which we had not been able to examine 
properly owing to bad weather, and returned to Suva, having steamed 
a little over thirteen hundred miles.? 

While we were exploring the reefs in the vicinity of Suva, the 
“ Yaralla’? made two trips in charge of Captain Thomson, one to the 
Nandi waters entering through the Navula Passage, extending as far 
north as the Waia Islands.to the south of the Yasawa group; the other 
passing close to Vatu Vara, Yathata, and Naitamba, on the way to Wai- 
Jangilala in order to bring back the crew left there to carry on the boring. 


THE PELAGIC FAUNA OF FIJI. 


I brought with me deep-sea tow-nets of the various patterns used by 
the Prince of Monaco, by Dr. Giesbrecht of the Naples Zodélogical 
Station, and by Hensen on the “ National” Expedition, in order to com- 
pare their efficiency with the Tanner deep-sea self-closing net in use on 
the ‘ Albatross,” and which I have adopted on my various expeditions. 
Unfortunately, our time in Fiji was so limited and the conditions for 
towing at great depths are such, among so many intercepting islands, 
that the results likely to be obtained seemed to make it unadvisable to 


1 The Islands and Coral Reefs of the Fiji Group, by Alexander Agassiz, Am. 
Journ. Sci., Vol. V., February, 1898. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 15 


devote the time necessary for such a comparison. So nothing was done 
to test the comparative efficiency of the various deep-sea self-closing 
towing nets. When practicable we collected on the reef flats of various 
islands and atolls. 

A number of hauls were made with the deep-sea Tanner net at 
several points in Fiji, such as the Strait of Somo Somo, off the Matangi 
Passage, off the west face of Nukusemanu Reef, off Blackswan Point, off 
the north point of Vatu Leile, across the eastern opening of Mbengha 
Passage, and off Suva Harbor. The depth at which we towed varied 
between one hundred and seventy-five fathoms and thirty fathoms to 
the surface. At the localities where each deep haul was made, a surface 
haul was also made. We were rather disappointed in the character of 
our catch. There were no great novelties ; the number of Medusz was 
usually quite small, but we obtained a large number of Crustacea. 

The contents of the nets varied but little at the different localities. 
We obtained young Fishes, Fish eggs and Salpz, Doliolium, Alcyopide, 
Copepods, Squillee, embryos of Macrurans and Brachiurans, Sapphirina, 
Sergestes, Euphausia, several species of pelagic Macrurans, and Rhegma- 
todes, Halopsis, Agalma, the bell of a large Siphonophore unknown to 
me, Tamoya, many Diphyes, Ectoplenra, Oceania, Berenice, Liriope, 
Polygordius, Tomopteris, Octopus, Mollusk embtyos, Hyalea, Atlanta, 
Styliola, Tiedemannia, and other Pteropods. In fact, the pelagic fauna 
seemed singularly like that of the Straits of Florida, but far less 
abundant. 

Mr. Mayer made also a number of surface hauls, and collected many 
species of Acalephs which had escaped the large tow-net, two species 
of a Rhizostome, a Eucharis, an Aurelia, and an Idya. The Sagitte 
we collected were unusually large ; Collozoon was quite abundant, and 
occasionally we collected Globigerine of a reddish tint, and other 
Foraminifera. 

During our cruise we constantly passed long windrows of Algze torn 
from the reefs, extended patches of a yellow Trichodesmium, and masses 
of leaves and flowers, and branches of all kinds of trees, floating at the 
mercy of the winds and currents. 

It is interesting to note that the surface hauls made during our 
trip have developed the fact that the majority of the genera of Acalephs 
collected in Fiji belong to the same genera as those found on the east 
side of the Isthmus of Panama. The great geographical range in the 
Pacific of many of the genera of Echinoderms and of Crustacea as well 
as of Fishes found in the West Indies has already been noted. The col- 


16 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


lections of Acalephs made by the “ Albatross” in 1891,1 and those we 
have made in Fiji, show a remarkable similarity between the West In- 
dian Acalephian genera and those of this part of the Pacific. We found 
in Fiji Linerges, Polyclonia, Aurelia, Halopsis, Tiaropsis, Gonionemus, 
Liriope, Bougainvillia, Eutima, Oceania, Aglaura, Eucharis, Idya, Agalma, 
two genera of Diphyes and Physalia, all genera occurring in the Gulf of 
Mexico. This will be brought out in greater detail by Mr. Mayer, who 
has in preparation a paper on the Acalephs of our Southern States, . 
which will appear somewhat later than his report on the Acalephs col- 
lected at Fiji. This similarity will undoubtedly be found to extend to 
other groups of pelagic animals. 

We were fortuuate enough to be at Levuka at the time of the appear- 
ance of the “ Bololo.” On the morning of the 17th of November we 
left the ship at three o’clock, bound fora spit named Bololo Point, 
about three miles south of Levuka. We had scarcely reached the spot 
when our guide put his hand in the water and pulled out one of the 
worms. Ina few minutes the water was full of them, canoes put out from 
_ the shore, men, women, and children were wading on the reef exposed 
by the tide, with nets, and all kinds of utensils to catch Bololo. As the 
light increased, the Bololo increased, and at one time they were so plen- 
tiful that the water surrounding our boat must have been filled with them 
so thickly as to resemble vermicelli soup. A bucket put overboard 
seemed to contain nothing:else. We made an excellent collection, and 
preserved a large number by different methods. We found, as we had 
expected, that their sudden appearance was connected with spawning ; 
there were males and females swimming about full of eggs and of sperm. 
When in captivity they soon discharged these, the water became milky, 
and masses of dark eggs were left on the bottom of the dish. With the 
escape of the eggs came the collapse of the worm, and nothing was left 
but an empty skin scarcely visible. Thus the Bololo seems suddenly to 
disappear. The males are light yellowish brown, the females dark green. 
Their activity is something wonderful, and the bursting of the animal 
when it discharges its eggs is quite a peculiar phenomenon. 

Dr. Woodworth made it an object to collect all the material that 
could be got together in regard to the Bololo, and he will prepare a 
paper on these interesting Annelids. 


1 Reports on the Dredging Operations off the Coast of Central America, Mexico, 
off the Galapagos, and in the Gulf of California, in Charge of Alexander Agassiz, 
by the U.S. Fish Commission Steamer “ Albatross,” in 1891, in command of Lieut. 
Com. Z. L. Tanner, U. 8S. N.—XXI. Die Acalephen, von Otto Maas, Mem. Mus, 
Comp. Zool., Vol. XXIII. No. 1, 1897. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 27 


CLASSIFICATION OF THE ISLANDS OF FUT, 


It will greatly facilitate understanding the relations of the islands 
and coral reefs of Fiji, if we follow in their description a classification 
which will bring together islands and reefs of identical or similar geo- 
logical structure. 

We may take at first such volcanic islands as Koro, Ngau, and pass 
to the larger islands like Taviuni-and Kandavu, finishing that class of 
islands with descriptions of Mbengha, Komo, and the like. We will 
take up next islands and reefs composed wholly of elevated coralliferous 
limestones like Marambo, passing to such islands as Namuka, Ongea, 
Fulanga, and to such reefs as Wailangilala and Ngele Levu. Next the 
island groups in which we find both volcanic and coralliferous limestones, 
such as Lakemba, Mothe, Vanua Mbalavu, Kimbombo, and the like, 
the two large islands of Viti Levu and Vanua Levu being treated sepa- 
rately. This will be followed by an account of the islands and reefs we 
did not examine, and finally by a sketch of the atolls, the geological 
structure of which could not be determined, and which might owe 
their origin to banks of submarine erosion, derived either from volcanic 
or from elevated coralliferous limestone islands. 

Undoubtedly the islands of Fiji, whether of volcanic origin or of 
limestone, would vary greatly in the height to which they had been 
elevated. Naturally, the volcanic islands would be denuded and eroded 
to a less extent than the limestone islands, and the comparison of the 
islands in Lau might give us some idea of the extent of this erosion 
and denudation. The volcanic islands, consisting mainly of breccia, 
are of course far more rapidly eroded than if they consisted of compact 
voleanic rocks. 

Of course some of the islands which have been named here as vol- 
canic or as composed of tertiary limestones may prove on more extended 
examination to be composite islands, and in the rapid visit made to some 
of the islands we may not always have discerned their most character- 
istic features. Yet in a general way steaming between the islands, one 
cannot fail to be struck with the totally different aspect of the volcanic 
islands and of the islands composed of elevated limestone. A mere 
glance is sufficient to distinguish the rounded and gradual voleanic slopes 
(Plates 46, 51, 57, 58) from the flat-topped summits and precipitous 
cliffs characterizing the limestone islands (Plates 75, 76, 79, 86, 88, 90). 

Gardiner has, as we have, classified the islands of Fiji into elevated 


limestone islands, into elevated limestone and partly volcanic, and into 
VOL. XXXIIT. 2 


18 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


voleanic,' a division which Lister had previously applied to the Tonga 
group. Gardiner was, as we were, struck with the difference in the 
physiognomy of the islands, the volcanic islands, with their gentle slopes, 
rounded summits, or conical peaks, being in striking contrast to the flat- 
topped hills with precipitous sides, and the glistening white cliffs of the 
islands consisting of elevated coralliferous limestones. 

I obtained from various localities in Viti Levu specimens of the 
older crystalline rocks belonging to the same series, which, according to 
Wichman ? and Horne, have a very considerable extension both in Viti 
Levu and in Vanua Levu. The tufas and conglomerates are in many 
instances fossilliferous, and are considered by Martin as tertiary, not 
older than miocene. Wichman concludes that the larger islands must 
have existed as a continent during mesozoic and paleozoic periods, and 
that oscillations of level only took place in latest tertiaries. From the 
specimens examined by him, Wichman also concludes that Kandavu, 
Ovalau, Ono, and some of the Exploring Isles consist principally of 
andesites and basalts, and their tufas. According to Horne, Taviuni 
_is the only island of the group which is of purely volcanic origin. This 
certainly is not the case. I would mention, among others, Moala, 
Thombia, and Totoya.® 


VOLCANIC ISLANDS. 


Koro. 


Plates 3*, 19*, Fig. 8. 


Koro is one of the larger volcanic islands which has not been greatly 
affected by submarine erosion. It is about ten miles long with a north- 
ern face of five, the east and west sides run toa point. The shores, 
with the exception of the southern part of the west coast, which runs 
nearly north and south, are bordered by a fringing reef extending about 
a mile and a half from shore; on the east coast the fringing reef is cut 
into small incipient lagoons (Nangaidamu Harbor), and has several boat 
harbors, generally opposite the mouth of a small river. On the north 
coast the reef patches extend nearly four miles from shore, forming an 


1 Proc. Camb. Phil. Soc., Vol. IX. Part VIII. p. 457 (1898). 

2 Min. u. Petrog. Mittheil. v. Tschermak, Vol. V. Pt. I. p. 1 (1882). 

3 The specimens of rocks we collected in Fiji at the different islands are now 
under examination, and a report on them will follow later. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 19 


indistinct lagoon called Stone Axe Roads. The northeastern extension 
of the east coast fringing reef forms an open roadstead. This spur is 
covered with magnificient patches of coral in from one to three fathoms. 
One can trace from the long line of lava negro-heads — some of these are 
quite large — covering the reef flats, the former northern extension of 
the island. We could also trace to the south the low bluffs from the 
erosion of which have been formed the flats upon which the fringing reef 
has found a footing. A very strong current was flowing over the spur of 
Nathomaki Point, driven westward by the easterly trades. 

The principal ridge of the island runs transversely across it from the 
southern point to its northeastern end. Its highest point is over 1,800 
feet. ‘The faces of the island are furrowed by deep valleys. 


Mbatiki. 
Plate 12. 


We did not land on Mbatiki, but steamed close enough to the shores 
to obtain some idea of its characteristic features. The highest peak on 
the northern side is a little over 600 feet. There are two deep indenta- 
tions, one on the west, the other on the south side. It is surrounded by 
a shore fringing reef from three points of which spurs extend parallel to 
the shore, impounding three narrow shallow lagoons with a depth of 
from three to five fathoms. The lagoons are full of coral heads. There 
are boat passes into two of the lagoons. The island is of volcanic 
origin. 


Moala. 
Plates 16, 57. 


Moala is an island of volcanic origin, triangular in form, the eastern 
face indented by a deep bay, fully two miles long, by about three 
fourths of a mile in width, with sixteen fathoms in greatest depth. The 
highest point of Moala is over fifteen hundred feet. The ridges sur- 
rounding the deep bay have the appearance of being the rim of an 
extinct crater (Plate 57), broken to the eastward, some points of which 
rise from over twelve hundred to over fourteen hundred feet, the bay 
forming the bottom of the extinct crater. 

The western part of the north coast is edged by a fringing reef extend- 
ing nearly a mile off shore ; towards the east the fringing reef proper 
becomes quite narrow, while disconnected coral patches of considerable 


20 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


width extend towards the northeast extremity of the outer reef. The 
outer reef flats are narrow, and run in a southerly direction, forming an 
elbow opposite the eastern point of the island at a distance of from one 
to two miles, and enclosing the lagoon off the eastern face of the island, 
the continuation of the deep bay. South of the deep bay the outer reef 
nearly connects with the edging reef of the island, leaving a passage 


DEEP BAY, EAST FACE OF MOALA. 


across the outer reef about a mile in width, the southern horn of which 
extends about three miles to the south, then in a westerly direction, 
then north until it strikes spurs of the fringing reef on the northwestern 
coast of the island, where the outer reef forms in connection with the 
fringing reef a series of reef flats full of coral patches and heads. The 
lagoon to the southwest of the island is also full of coral patches and 
heads, some of them of considerable size, which extend to Herald Road- 
stead, the northeastern part of the lagoon, which alone is comparatively 
free from obstructions. Owing to the presence of so many patches and 
heads the depth in the lagoon is most irregular. In Herald Sound it is 
as great as twenty-five fathoms, and somewhat less off the southwest 
and northern coasts. The characteristic heads which crop out from 
the shore at so many points are well illustrated by the heads composed 
of voleanic rocks which form the spit protecting the anchorage to the 
west of Naroi village, on the north shore of the island. Wherever we 
dredged we found that the bottom inside the lagoon consisted of fine 
voleanic mud mixed with coral ooze and broken shells. , 

There are two entrances to the lagoon on the east face, one opposite 
the deep bay, the other to the south, while on the west there is an 
entrance to Herald Sound (the lagoon of the southwest side of the 
island) near its northern extremity. 


——_ 


* 
AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 21 


Ngau. 
Plates 12, 13, 11°, Figs. 1-3. 


Negau Island is about eleven miles long, by an average of nearly four 
miles in width. It consists of volcanic rocks; a high ridge runs along 
the middle with spurs separated by deep valleys extending towards the 
east and west coast. One of these spurs forms a deep bay on the north- 
western coast. The peaks of the main ridge vary in height from 1,000 
to over 2,300 feet. Ngau is protected on the east and north by a 
broad fringing reef of a width of over three miles. At the northern 
extremity and on the east face there are a few reef boat harbors, cut out 
of the fringing reef which also extends along the whole western shore as 
a very narrow fringe. As will be seen from the chart (Plate 13), the 
small .reef harbors are without exception off the mouth of the moun- 
tain streams both on the north and east faces of the island; these in the 
rainy season bring down a large amount of mud and prevent the growth 
of corals at their mouth. From the southern end of the island extends 
in a northwesterly direction an outer barrier reef, varying in width from 
a quarter of a mile to three quarters of a mile. This reef is continuous 
being only broken in the middle by a narrow ship passage. The general 
depth of the lagoon is about twenty fathoms, with a greatest depth of 
twenty-nine. The western reef sweeps round the northern face of the 
lagoon, its eastern extension becomes broken into disconnected patches, 
and the greater part of the northeastern bay of the lagoon is filled with 
coral patches which connect it with the fringing reef of the north shore 
of the island. There are also numerous patches in the southern bight 
of the lagoon, and along the inner edge of the outer reef near the north- 
western elbow of the reef. As far as we examined the reef of Ngau the 
reef flat was covered with most extensive patches of thriving corals. 

There is a small island, Yathiwa, on the very edge of the reef forming 
the southern horn of Ngau. It holds to Ngau very much the same rela- 
tion which Kobu Island does to Nairai, but is nearer the outer edge of 
the reef, while Kobu is in the lagoon surrounded by comparatively deep 
water. 

Mambulitha Reef. 


To the south of Ngau we could see the breakers giving the outline of 
Mambulitha Reef (Plate 12), separated from Ngau by a channel having 
a depth of 750 fathoms. This reef is pentagonal in outline, about one 
mile and a quarter long, is awash, has no opening, and encloses a shallow 


‘ 


bo 


2 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


lagoon of pale green water, the sea breaking heavily upon the edges. I 
consider this reef as having been denuded and eroded to its present stage, « 
which precedes that of a more sunken atoll, like Adolphus Reef, with a 
deeper lagoon. 
Nairai. 
Plate 11%, Fig. 4, and Plates 12, 14, 58, 59. 


Nairai is a volcanic island, triangular in shape (Plates 12, 14), with 
sides of about four miles in length. Its central ridge forms an open are 
to the east, its central peak rising to a height of over eleven hundred feet 
The western slope of the island is much less steep than the eastern side. 
(Plate 58.) The island is edged by a narrow fringing reef, with the 
exception of the most western point, where it expands into a broad 
fringing reef, the outer patches of which extend into the outer encircling 
reef. The encircling reef surrounding the island is a narrow reef flat, 
from a quarter to a mile distant from the eastern side, and from one to 
one and a half on the western side. But the prolongations of the horns 
of the outer reef to the northeast, south, and west are from four to five 
miles distant, forming thus three lagoons separated by long passages. 
(Plate 14.) The greatest depth in the lagoons is twenty-six fathoms off 
one of the western passages. The general depth is from ten to fifteen 
fathoms. The inner edge of the eastern outer reef is fringed with coral 
patches. This part of the reef is continuous, having only one boat 
entrance nearly opposite the southern extremity of the island. The 
western reef has two deep passages, and a boat passage near the south- 
ern horn of the atoll. This as well as the other points of the outer 
reef, both at the northeastern and northwestern horns, are studded with 
coral patches. The greater part of the lagoon, extending from the 
northern part of the island to the Nayatha Passage, is studded with 
rocks and coral patches, undoubtedly the remnants of fragments of the 
main island, which crop out in every direction within the lagoon, and as, 
negro-heads upon the reef flats. Naikobu (Plate 59), or Magnetic Island, 
a small island to the south of Nairai, is one of these outlyers; it is 
ninety feet in height, the base running into ten fathoms, and is covered 
with corals. It is further remarkable for the great variation it causes 
to the compass. We observed on the top a westerly deflection of 87°. 
The bottom of the lagoon consists of fine coral, coralline sand, and broken 
shells, which form large white areas separating the coral patches and 
the numerous patches of coralline alge which flourish upon the floor of 
this lagoon wherever we examined it. The corals of the fringing reefs 
of both Nairai and Ngau were growing specially vigorously. 


—— eS a 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 23 


Makongai and Wakaya. 


Plates 37, 11°, Fig. 9 ; Plates 3”, 11°, Figs. 7, 8, and Plates 15, 55, 56. 


Makongai and Wakaya present features nearly identical. 


They are 


both long lines of narrow reefs, enclosing in the one case an irregularly 
triangular lagoon open on its northern face, and in the other an irregu- 


larly shaped parallelogram, with 
undulating sides and rounded 
corners. The island of Makongai 
is somewhat rectangular, with 
many indentations; it is of vol- 
canic nature, and attains a 
height, of nearly 900 feet. On its 
eastern face the encircling outer 
reef becomes its fringing reef at 
several points. It is separated 
by a narrow channel having a 
depth of twelve fathoms from 
Makondranga, a small island sim- 
ilar in structure to Makongai, 
about half a mile from the outer 
reef. The whole eastern encir- 
cling barrier reef is broken up 
into a number of small patches 
with boat passages between them. 
With the exception of one boat 
passage the western reef forms a 
continuous line of breakers, but 


NORTHWEST POINT OF MAKONGAT. 


on the northern side the reef patches are limited to rocks, grown over 


LEDGE OFF MAKONGAI, 


at the base with corals, judging from those we saw while passing into 


the lagoon, 


24 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY, 


Makongai is edged with a fringing reef. The islands in the Makongai 
lagoon are in the northeast corner close to the#astern face of the outer 
reef. The lagoon has a general depth of from thirteen to seventeen 
fathoms, with a greatest depth of twenty-one fathoms in the northern 
part. The southern part of the lagoon is full of coral patches, remnants 
of islands and islets similar to those of the small island of Tambaka, still 
connected with Makongai by a neck of boulders, which reaches to the 
westward as an extensive flat, and fringed below low water mark with 
flourishing patches of corals. Such a patch with a few angular blocks 


= SaaS S— 


LEDGE OFF MAKONDRANGA. 


still visible above high water mark, lies off the southwest point of 
Makondranga, and many others off the southeastern face of Makongai. 
Corals within the lagoon grow in from seven to one or two fathoms. 
The rest of the bottom of the lagoon consists of coral and coralline 
sand. 

Makongai and Wakaya are connected by a narrow reef ridge about a 
mile in length. The island of Wakaya is nine miles long, triangular in 
shape, tapering to a point, and situated close to the western edge of the 
outer reef of the lagoon. A fringing reef edges its eastern face, while 
the extension of the outer reef forms the wider fringing reef of the 
western shore. ‘Towards the south this part of the fringing reef encloses 
two secondary lagoons, one of which has a depth of five fathoms. The 
southern part of the outer reef is continuous ; the northeastern face is 
broken by several passages, and there are three to the north of Wakaya 
on the western face. The highest point of Wakaya is nearly 600 feet, 
forming a range of steep bluffs along the northern part of the island, 
which slopes very gradually to the east. The southern part of the island 


a 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 25 


is not more than 300 feet high, and is joined to the rest of the island by 
a comparatively low neck. The depth of the Wakaya Lagoon is greater 
on the average than that of Makongai; it reaches a maximum depth of 
thirty-six fathoms, with a general average depth of over twenty. There 
are comparatively few patches in the lagoon. The bottom consists of 
coralline sand and shells. We entered through the northern passage 
and crossed the lagoon, and on our way out examined the reef patches 
forming the boat passages to the south of it. On the shore of the bay, 
near the boat passage, we found a good deal of pumice. We found 
traces of elevation on the neck connecting the point on which Lieutenant 
Langdale’s house is built. 

We could not examine the corals on the weather face of the weather 
reef, but on the inner side and on the lee reef we found corals flourishing 
most luxuriously, mainly Madrepores, Pocillopores, Astreans, Mzeandrinas, 
Fungiz, and a few Gorgonians. They form a belt mainly between two 
and seven or eight fathoms, beyond which there seem to be only coral 
sand and corallines both on the inner and outer faces of the lee reef. 
With the disappearance of Wakaya through denudation and erosion, we 
should have an atoll with a substratum of volcanic rocks which very 
likely might be covered to a limited depth with islets of coral sand blown 
up from the encircling reef, — an atoll in no way to be distinguished by 
outward appearances from the theoretical atoll built up by corals and 
by subsidence. 


Mbengha. 


Plates 8, 11°, Fig. 5, and Plates 46-49. 


Mbengha Island is irregularly shaped, with three deep indentations, 
one on the western side, the others on the eastern, nearly cut off the 
high point forming the eastern side of Malumu Bay from the main body 
of the island. (Plate 48.) The principal ridge, running nearly north 
and south across the central part of the island, rises abruptly from the 
south to a height of over a thousand feet, and has several peaks at- 
taining heights varying between 1,200 and over 1,400 feet. The secon- 
dary ridge to the east of Malumu Bay is somewhat less than a thousand 
feet. On the east face to the south of Solianga are exposed some fine 
bluffs consisting of volcanic conglomerate breccia. (Plate 46.) They 
are perhaps as good examples as we have seen of the great erosion and 
denudation which have taken place in this part of the Fiji group. 

A more detailed view of the appearance of the volcanic rocks of 
Mbengha is given in Plate 47, an eroded shore bluff immediately in 


26 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


the rear of the beach at Rukua on the west side of Mbengha. Similar 
volcanic breccia bluffs are characteristic of many points in Fiji. 

In adition to the main island there are three other islands. Moturiki 
and Stuart, which are small satellites of Mbengha, and Yanutha, a larger 
island near the western edge of the lagoon. These islands have the 
same geological structure as that of Mbengha. (Plate 8.) 

Mbengha is on the eastern point of the lagoon, separated from the 
inner edge of the outer reef by a channel varying in width from a half to 
one and a quarter miles, with a greatest depth of twenty-three fathoms 
closer to the island than to the reef. The channel between Yanutha 
and the outer reef is about three quarters of a mile in width, with a 
depth of from eleven to thirteen fathoms. There are in addition a 
number of patches of coral rising from a depth of from ten to twelve 
fathoms, irregularly scattered over the western part of the lagoon and 
along the inner edge of the outer reef. 

Mbengha and Yanutha Islands are enclosed within a long reef over 
thirty miles in length, forming an irregularly shaped pentagonal lagoon 
with rounded angles. The northern side is open, forming a passage fully 
five miles wide, and studded with patches. This part of the lagoon slopes 
very gradually from 17 fathoms to 130 or 140 fathoms in the centre 
of the Mbengha Passage, separating Mbengha from the island of Viti 
Levu. 

The northeastern face of the lagoon is flanked by the Pratt Reefs, those 
upon which the low sandy Storm Island is placed, and the Nanuku Reef. 
There are several passages available for vessels on that side of the lagoon. 
The Nanuku, Sulphur, and Cutter Passages with a depth of from nine 
to thirteen fathoms. The southern and southwestern sides of the lagoon 
are flanked by a long unbroken coral reef, the Mbengha Barrier Reef, 
varying in width from half a mile to over a mile and a quarter, extending 
from Cutter to Frigate Passage. There is a small sand key about the 
middle of the Mbengha Reef on its inner edge. To the north of Frigate 
Passage the Yanutha Reefs form the northwestern side of the Mbengha 
Lagoon. They are separated by broad channels ending in the reef of Bird 
Island and a long line of patches, the Nisithi Rocks, which form the western 
spit of the wide opening on the northern side of the lagoon. As will be 
seen from the chart, the bottom of the Mbengha Lagoon is most irregular ; 
it is very uneven, varying greatly in depth, and full of heads and patches 
overgrown with corals. The rocks and heads and patches are fragments 
of volcanic rock, the remnants of the island of Mbengha when it ex- 
tended over the greater part of the area now enclosed by the outer reef, 


ee 


| 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. rtf 


——remnants left from the disintegration and erosion of the former greater 
Mbengha. 

The bottom in the lagoon is a mixture of volcanic mud and coral sand 
in the vicinity of the islands, but as we proceed towards the reef it car- 
ries a greater admixture of coralline alge and of coral sand, and in the 
belt adjoining the inner edge of the outer reef is made up entirely of 
fragments of coral, of coral sand, and of coralline alge. In the central 
parts of the lagoon it is algee and corallines. 

The reef rises very gradually from seven fathoms to a depth of from 
two to three feet on the reef flat. This is covered with fragments of 
dead corals which increase in number towards the sea edge of the reef. 
The fragments are covered with alg, corallines, and nullipores, which 
cement them together. In depths of seven to eight fathoms heads and 
clusters of corals begin to grow. They are separated by wide lanes of 
coral sand, and as we rise on the slope of the reef they grow more closely, 
forming a wide belt of thriving corals from six to three or two fathoms 
in depth, when they grow less profusely, and finally pass into the wide 
flat area of the outer reef, made up of broken corals and fragments, and 
large masses thrown up on the sea face of the reef, which are gradually 
being broken up by the surf beating upon the reef flat. 

Storm Islet? (Plate 49) is an excellent specimen of a sand key 
thrown up by the waves upon the outer reef flats. It is somewhat 
less than three hundred yards 
long and about eighty yards 
wide. The beach is quite steep, 
protected by large patches of 
beach rock, which surround the 


southern extremity of the isl- 
and. The crest of the island 
is covered with cocoanut trees, screw pines, aud casuarinas, as well as 
with an outer fringe of bushes and shrubs. 

The greater part of the shores of Mbengha Island are edged with a 
fringing reef, and coral patches forming an irregular belt extend into six 
or seven fathoms in depth. As the sea breaks but little on the outer 


STORM ISLET. 


1 Dana has called attention (Coral Islands, p. 241) to the advantage which coral 
island accumulations have over other shore deposits, ‘owing to the ready aggluti- 
nation of calcareous grains,” and, as he suggests, with the formation of coral sand 
rocks along the beaches and reef rock in the water a rock defence against en- 
croachment is produced. So that limestone rocks thus formed will prove a most 
effectual barrier to the destructive action of the waves. 


28 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


Mbengha Reef, I was able to examine the sea face of the reef, ana 
found that in Frigate Passage both sides of the reef were flanked with 
large heads of corals beginning in from five to seven or eight fathoms. 
On the outer face, though corals were growing, there were no large 
heads, at about six fathoms we found Madrepores, Fungiz, Pocillopores, 
small heads of Porites, Astreans, and of Mzandrinas and Gorgonians. 
This belt extended to the line of breakers pounding upon the reef flat. 
Outside of six to eight fathoms the corals seem to have disappeared, as 
the lead brought up nothing but coral and coralline alge sand. 


Kandavu. 


Plates 10, 11, 50. 


The extent of the erosion and denudation which has taken place 
along the coast of Kandavu is well exemplified by the John Wesley 
Bluffs near the village of Tavuki (Plate 10), and similar bluffs rising 
to the westward of Tavuki Bay. The John Wesley Bluffs (Plate 50) are 
a line of nearly vertical cliffs of volcanic origin cut into wide rounded 
lamellar masses, rising to a height of fully 500 feet on the east side of 
Tomba ni Tavuki. A part of the hill slopes on the west side of the bay 
are covered by the rounded tops of similar rocks cropping out on the 
surface, giving the slope the appearance of a graveyard crowded with 
dome-shaped monuments. | 

The heads studding the Bay of Tavuki, and forming the extension of 
the outer reef patches parallel to the coast, are covered with thriving 
corals, growing upon a substructure of volcanic rocks, as is clearly seen 
from the nature of the negro-heads cropping out in the bay. 

With the exception of the broad fringing reef stretching to the west of 
Tavuki, the north shore of Kandavu is edged by a narrow fringing reef 
(Plate 10), and from Yale Point to Tomba ni Richmondi an indistinct 
- barrier reef extends, made up of small distant patches, except where the 
Malatta Reefs enclose a wide bay north of John Wesley Bluffs, studded 
with coral patches and heads. The south shore of Kandavu is likewise 
edged with a narrow fringing reef in Soso and Kandavu Bays inside 
of the broad barrier reefs across their entrance. The islands and islets 
within the North Astrolabe Reef Lagoon are also edged with narrow 
fringing reefs. 

The platform of submarine erosion extending north of the eastern 
extremity of Kandavu is one of the best examples of its kind we find in 
Fiji. The great lagoon, with its islands and islets, represents a stage of 


— el 


ee 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 29 


denudation aud erosion somewhat more advanced than that existing on 
the eastern half of the south shore of Kandavu. 

We cannot fail to notice also the greater width of the shore platform 
wherever the coast has a northerly trend, as, for instance, west of Tomba 
ni Richmondi on the north coast, and north of the John Wesley Bluffs, 
where the platform is edged by the Malatta Reefs and studded with 
heads and patches. On the northern coast, however, the fringing reefs 
are narrow, while on the south coast of Kandavu (Plate 10) they take 
their greatest development, exposed to the full sway of the southeast 
trades. A glance at Plate 11 cannot fail to show the relatively great 
width of the eastern belt of the encircling reef, as compared with that 
of the western side of the Great Astrolabe Lagoon.’ In a smaller lagoon 
like North Astrolabe Reef, where the breakers pour over the eastern 
face, and water flows constantly over the western edge, the difference 
in the width of the reef on the two sides is not so marked. 

While undoubtedly the width of a reef depends in great measure on 
the nature of the platform upon which it grows, yet I do not see the 
force of Lendenfeld’s statement,” that while “lateral growth of corals no 
doubt takes place, it is not the actual cause of the formation of the 
great coral reefs.” There certainly is nothing to prevent the swarms of 
embryos which float at certain times in the vicinity of a coral reef from 
attaching themselves and growing upon any surface within reach having 
the proper depth on both sides of any growing reef. Undoubtedly the 
extension within the lagoon, both in barrier reefs and atolls, of the coral 
heads is due to such a cause, and the wider the reef the closer do the 
heads come together as we pass upon the reef flat from the inner edge of 
the reef towards the outer margin. In an account of a discussion on 
coral reefs® by Sollas, Hickson, Rothpletz, and others, Stebbing stated 
that young corals might start on either rising or subsidence, but only 
subsidence is favorable. That, it seems to me, depends entirely on the 
depth at which they start; they may have 120 feet, and build up a reef 
of that thickness, which is fully as thick as most reefs we know anything 
about. 


‘ 

1 T cannot agree with Gardiner in his statement that the windward reefs of Fiji 
are of about the same breadth. (Joc. cit., p. 492.) Compare the windward reefs of 
Mbengha, of the Great Astrolabe Reefs, and of the east coast of Viti Levu with the 
windward reefs of Wakaya, of Nairai, of Totoya, of the Budd Reef, of Kanathea, 
of the Exploring Isles, of the Argo Reefs, of Lakemba, of Aiwa, of Mothe, and of 
Ongea; the latter are certainly as a rule much narrower than the former. 

2 Nature, Vol. XLII. p. 31. 

3 Nature, October 12, 1893, p. 574 


30 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Murray, who visited Kandavu in the ‘ Challenger,” considers the 
banks of Fiji surrounding the extremities of volcanic islands as banks 
formed from the loose material of the islands spread out laterally by 
wave action, the extensive banks extending much farther seaward 
there in one direction than in another. Murray has also called attention 
to the North Astrolabe Reef, which, if its present condition with Solo 
Rock in the centre is due to subsidence, should have a very much deeper 
lagoon, instead of the comparatively shallow one characterizing that 
reef. 


Great Astrolabe Reef. 


Plates 11, 11°, Figs. 10-13, and Plates 51, 52. 


To the northward of the eastern extremity of Kandava (Plate 11) ex- 
tends the Great Astrolabe Reef. Its eastern face is the extension of 
the reef to the eastward of Tomba ni Soso (Plate 10), an irregularly 
shaped bay, the mouth of which is protected by a barrier reef. This 
barrier reef extends as a fringing reef along the southern coast as far 
as Kandavu Bay, where it becomes separated from the island and forms 
stretches of barrier reef patches, with passages leading into the bays 
protected by the reef. 

West of the entrance to Ngoala Harbor a broad fringing reef extends 
along the southern coast nearly to the western spit of Kandavu. Sev- 
eral reef harbors are cut out from it, one of which, Tomba Yauravu, is of 
considerable size (Plate 10). From Naingoro Pass the outer reef of the 
Great Astrolabe Reef runs unbroken in a northerly direction for a dis- 
tance of 25 miles round its northern horn, as far as Usborne Pass, which 
is an entrance into the lagoon on the western side, about a mile from the 
apex of the Great Astrolabe Reef. Off Mbulia, the easternmost of the 
islands inside the Great Astrolabe Reef, the eastern encircling reef 
makes a sharp elbow, and then forms a double curve in a northwesterly 
direction to the narrow apex, from which the reef turns sharply south 
as far as Alacrity Rocks in a great narrow are broken in many places. 
North of Ono Island there are three well defined passages, but south of 
Alacrity Pass the reef becomes much broken up into small patches, 
and finally, from Ono Island south the lagoon is open, and has a steep 
slope towards the 100 fathom line. 

The depth of the lagoon north of Ono is not more than twenty-two 
fathoms ; the bottom is most uneven, often passing rapidly from five 


1 Nature, July 4, 1889, p. 222. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 31 


or eight fathoms to seventeen and eighteen fathoms, with a number of 
extensive patches, the remnants of former islands now covered with 
coral. (Plate 11.) 

Within the Great Astrolabe Reef are included a number of islands 
and islets. They are all volcanic in structure, and all bear signs of the 
great denudation and erosion to which they have been subjected. Be- 
ginning at the north there is Vanua Kula, about 250 feet in height, 
covered by scanty vegetation; next comes Ndravuni, a much larger 
island, rising to a height of 350 feet. Yanu Yanu sau and Yanu Yanu 
eloma are small islets upon a spit which must have formed a part of 


NMARA AND YANU YANU ELOMA. 


Nmara Island ; to the south of it is Ngasi Mbali. To the eastward 
are Yaukuve and Yaukuve lai lai (Plate 52), 400 and 200 feet respect- 
ively, connected by a spit, and off the south point of Yankuve lai lai 
extends a long sunken shallow rocky spit. Mbulia and Yambu are to 
the north of Ono, the largest of the islands within the Great Astro- 
labe Lagoon (Plate 51). It has two peaks of over 1,100 feet, and is 
indented with deep bays forming finger-like spokes, which further dis- 
integration would soon separate as distinct islands, similar to those of 
Vuro and Vuro lai lai off the northeastern point of the island. Between 
Ono and the eastern point of Kandavu Island the lagoon is dotted with 
numerous rocky and coral patches. Ono, and most of the islands of 
the Great Astrolabe Lagoon, are edged with fringing reefs. The eastern 
reef flat is quite broad (Plate 11) ; in some localities it is nearly a mile 
wide, besides being fringed along the inner edge by nearly continuous 
patches of rocks and corals. On the western face of Ono there are some 
fine cliffs, interesting as showing the progwess of the denndation and 
erosion to which the island has been subjected. It seems comparatively 
simple to follow with the chart the changes which must have taken place 
in separating from Kandavu the islands enclosed within the Great As- 
trolabe Lagoon north of that island. They undoubtedly represent the 
fragments of the former northern extension of Kandavu itself, which 


32 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


probably covered the greater part of the area now enclosed by the Great 
Astrolabe Reef. 

If we examine Kandavu Island itself (Plate 10), we can easily see 
how far denudation and erosion, if continued, would cut it up into a 
number of larger or smaller islands ; as, for instance, an island would be 
formed at the neck separating Tomba Kaivala from Koro Levu, a larger 
island, by the cutting of the neck separating Tomba ni Ndaku on the 
north side from Tomba ni Soso on the south of the island. Finally, the 
cutting of the Malatta Isthmus would make two islands of considerable 
size of the western half of Kandavu, while the many spits bounding the 
deep bays of the island would also become islands similar to Matanuku 
on the south side of Kandavu, and connected with it by the broad 
fringing reef. These would all be enclosed on the south by the southern 
extension of the Great Astrolabe Reef, which is now either a barrier or 
a fringing reef along the south coast of Kandavu, while on the north 
coast the island would merely be flanked by outlying reef patches sepa- 
rated by great stretches bare of reefs, as along the southwestern part of 
the Great Astrolabe Lagoon. 

Skirting the northern shore of Kandavu from Tomba Kaivala to 
Levuka, we found the physiognomy of the larger island to be identical 
with that of the islands of the Astrolabe Lagoon, — high cliffs, formed 
by the crumbling of the faces of the shores, sloping to high mountains, 
deep bays extending far inland, and a vegetation identical with that of 
the adjoining islands. According to the position and proximity of the 
islands to the inner edge of the outer reef flat, we found the bottom of 
the Great Astrolabe Lagoon to consist of volcanic mud or of coral sand 
and coralline algze, or of a mixture of the two. 


North Astrolabe Reef. 


Plates 11, 11°, Fig. 14, and Plates 53, 54. 


North Astrolabe Reef is separated from the northern point of the 
Great Astrolabe Reef by the D’Urville Channel, which is about a mile 
wide, and with 190 fathoms coralline bottom in the middle (Plate 11). 

North Astrolabe Reef encloses an oval egg-shaped lagoon about four 
miles in length by three and a half in breadth, with a small rocky islet, 
Solo, situated nearly in the centre of the lagoon (Plate 11). The great- 
est depth of the lagoon is sixteen fathoms, with very undulating bot- 
tom full of rocky and of coral patches along the inner edge of the reef, 
and especially over the southern part of the lagoon. Solo is composed 


lal et 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 33 


of volcanic rocks, and has been very much eroded by the action of the 
sea (Plate 54). Corals grow upon its slopes, but they are not very 
flourishing, either there or upon the many patches found inside the 
lagoon, and which are separated by broad sand lanes, or by dark patches 
of nullipores and alge, with a few scattered coral heads. 

The reef enclosing the lagoon is continuous except on the north side, 
where there are two entrances into the lagoon, one with thirteen and the 
other with three fathoms in the channel. The inner side of the weather 
reef can be reached quite close to the breakers. There is from one and a 
half to two fathoms of water on the reef flat, which is covered by a great 
number of flourishing patches of coral, mainly Madrepores, Pociliopores, 
heads of Astreans and Meeandrinas, with a few Gorgonians. The patches 
are separated by wide areas of coral and coralline sand. Towards the 
inner part of the lagoon, as the water deepens, the coral patches are 
separated by masses of dead corals and of fragments. Dark patches of 
coralline Algze become more abundant, and the coral patches less fiour- 
ishing and more distant. On the outer edge of the reef, to the south 
of Beagle Passage, the reef flat is somewhat narrower than on the east- 
ern face, where it varies from 1,000 to 1,800 feet in width; it is coy- 
ered by one to two fathoms of water, and the coral patches appear to 
flourish upon its surface fully as luxuriantly as upon the eastern face. 
The corals descended in steps to ten or even eighteen fathoms, rising 
from the coral and coralline sand separating the heads. They were 
most flourishing in the belt of from six to ten fathoms in depth. The 
prevailing trades drive a strong current across the lagoon, and the 
water of the lagoon rushes out through the northern passages and over 
the western reef flats with considerable velocity. The bottom inside 
of the lagoon consists mainly of alge, of coralline alge, and of broken 
shells and fragments of coral. 

It is quite probable that the North Astrolabe Reef represents an 
eroded peak adjacent to the former greater Kandavu, of which Solo 
Rock is the only witness left (Plate 53). 


Budd Reef. 


Plates 4, 18, 70. 


Budd Reef (Plate 18) has a narrow outer reef of irregular shape, broken 
into many separate patches. These become quite distant on the south- 
ern side, leaving the outline of the reef indistinct. The lagoon, as 
well as the channels separating the islands enclosed within the outer 

VOL. XXXIII. 3 


34 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


reef are quite deep, with the exception of that part of the lagoon 
which lies south of Yambu and Yanutha and between Thombia and 
the northwestern edge of the outer reef. The deepest part of the 
lagoon is 47 fathoms and the average depth is between 35 and 40 
fathoms. 

In addition to Thombia, which is on the northern horn of Budd’s Reef, 
there are the islands of Yanutha, Yambu, Mungaiwa, Tai ni Mbeka, and 
Rara ni Tinka, which are in the central part of the lagoon. South of the 
central islands the lagoon is also studded with rocks, as well as in 


the southwestern horn of the lagoon. The islands and islets and rocks, ~ 


as well as many of the patches, are of volcanic origin. Yanutha, the 
largest of the islands, about a mile long and half a mile wide, rises to a 
height of 480 feet. It is connected by a coral reef with Mungaiwa Island 
and Mbeka Rock. 

The most interesting of the islands is Thombia (Plate 70), the crater 
of an extinct volcano, having an exterior circumference of about two 
miles. The crater is half a mile in diam- 
eter, with a greatest depth of twenty- 
four fathoms. The rim of the crater 
rises at its highest point in a dome of 
nearly 600 feet. On the northeast side 

WESTERN END OF THOMBIA. the horns of the rim are connected by a 

flourishing fringing coral reef about a 
fifth of a mile in length, the extension on the ridge connecting the horns 
of the fringing reef surrounding the island. Both the inner and outer 
slopes of Thombia are steep, and, except on the northwest side, we find 
over thirty fathoms within a short distance of the shore. 

One cannot fail, on seeing the coral reef growing on the denuded rim 
of Thombia with the enclosed deep lagoon having a depth of twenty-four 
fathoms, to revert to the old opinion that some of the lagoons of atolls 
represented the rim of extinct craters. There is, it seems to me, nothing 
unreasonable in the suggestion that many of the small round atolls, or 


others perhaps rising from great depths and isolated, represent the de- 
nuded rims of such extinct craters as Thombia, or it may be that, if of 
greater size, they may represent parts of such larger craters as Totoya, or 
of circular islands with interior Jagoons resembling extinct craters, like the 
Sound of Fulanga. It seems simple to imagine that, when these small 
extinct craters have been levelled down, and corals have obtained a 
footing, they may have formed such atolls as Pitman’s Reef, Motua 
Levu, Motua lai lai, Williamson Reef, Horseshoe Reef, and other similar 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 35 


atolls in Fiji. We must remember, however, that the formation of such 
atolls may also be accounted for as the result of the denudation and sub- 
marine erosion of a patch of elevated limestone, cut first into a sound, and 
then, with the disappearance of the outer rim, into a lagoon surrounded 
by a shallow reef flat ; or the same result may be accomplished from the 
wearing away of islets of volcanic origin enclosed within the outer reef, as, 
for instance, from the disintegration of the islets now left in such atolls as 
the Kimbombo Islands, Komo, and others, or of islets consisting of 
elevated limestone like the Aiwa Islands, Katavanga, Vekai, and others. 
The structure of the negro-heads occurring upon the outer reef flats, or 
their position near either a volcanic or an elevated reef region being the 
only guide as to the category to which belong such atolls as Thakau 
Mata Thuthu, Thakau Vutho Vutho, the Adolphus Reef, Dibble’s, Duff, 
and Bell Reefs, Thakau Tambu, Malevuvu, ete. 

Such a cluster as Budd Reef suggests an explanation for the for- 
mation of interior atolls, like those described by Darwin as occurring 
in the Maldive Islands, very different from the one suggested by him. 
Were Thombia cut down by erosion to the water’s edge or below, and 
changed into a small atoll, we should have a secondary atoll within the 
area enclosed by Budd Reef, and were the other small islands of the 
cluster summits of elevated limestone, and should they in their turn be 
cut down, they might form in such a large lagoon as that of Budd Reef 
other diminutive atolls, or small atolls enclosed within an atoll. Such 
interior atolls, if my view of the formation of atolls is correct, could only 
be formed in lagoons of considerable depth and size, so that the seas 
formed by the prevailing winds should have a long sweep and rise to a 
considerable height, and thus possess great disintegrating power. I shall 
refer again, when describing Vanua Mbalavu, to the probable origin of 
such great depths as forty-seven fathoms inside of the reef encircling the 
islands of Budd Reef. 


Komo. 


Plates 19°, Figs. 9-11, and Plates 22, 63-65. 


Komo Island is a narrow ridge of volcanic origin, about-a mile and a 
half in length, rising to over two hundred feet. Its western extremity is 
connected by a coral reef full of voleanic negro heads, two of which are 
mushroom-shaped and of considerable size, with the islet of Komo Ndriti, 
itself about seventy feet high. Komo lies in the southeastern horn of the 
lagoon (Plate 22) close to the southern face of the outer reef flat, from. 


36 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


which it is only separated by a narrow boat passage full of negro-heads, 
especially numerous off the southeast point of the island. The lagoon 
enclosed by the outer reef flat is elliptical. There are two ship passages 
through the north face of the outer reef. The northern and eastern reef 
flats are narrow, edged on the outer side by masses of negro-heads ; while 
the western and southern reef flats are fully half a mile broad, and edged 
by an inner belt of heads, the central part of the lagoon is quite clear of 
them. The rocks were composed of a volcanic puddingstone (Plate 64), 
much like that of Mbengha, Levuka, and elsewhere. This disintegrates 
readily, is easily undercut, as we had ample proof in the undermining of 
the shore bluffs and the formation of so many negro-heads on the reef 
flats and off the spits of the island (Plate 63). The aspect of the islands 
of volcanic origin and of elevated limestone is quite different as seen 
from the sea. The mode of disintegration and erosion of the two kinds 
of material can at once be distinguished from the peculiar physiognomy 
of the rounded bluffs when composed of rocks of volcanic origin, or of 
the vertical shore bluffs deeply grooved and streaked with red earth, 
or eroded into domes or conical hills when composed of elevated coral- 
liferous limestone. 

The reefs which encircle Mbengha, Komo, and Budd Reef, indicate 
approximately the land area once probably occupied by those islands. 
The islands must have been of considerably greater height ; they have 
been reduced by denudation, and their area has been further diminished 
by extensive submarine erosion wearing away the ridges and spurs of the 
volcanic islands, and leaving submarine platforms of varying width, — 
dependent upon the nature of the material to be eroded, and the height 
of the land to be cut down, — upon the surface and outer edge of which 
corals established themselves. In the case of Komo and of Budd Reef, 
the islets which remain show the extent of the denudation and erosion. 
In the case of Mbengha the larger islands probably retain more of the 
character of the island which once covered Mbengha, representing its 
higher peaks, while the islets and rocks are all that remain of its lower 
ridges and slopes. 


Olorua. 


On our way into Komo we saw in the distance Olorua (Plate 22), a 
small island with a ridge having three prominent humps, probably of 
elevated limestone, rising to a height of 250 feet. The island is sur- 
rounded by a fringing reef extending to a point for more than a mile off 
the south face. A small lagoon full of heads separates the north shore 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. oT 


of the island from the narrow outer reef flat. We also passed the atoll 
of Thakau Vuite (Plate 22), separated from Komo by a channel of 
about one and a half miles in width, with a probable depth of about 
150 fathoms. The lagoon is about two 

miles and three quarters long by two ee atin ee 
miles broad, with a greatest depth of six- ns a 
teen fathoms; there is an opening for 
boats into the lagoon on the northwest side. The encircling reef flat 
is narrow, and there is a sand key on the northeast horn of the 


lagoon. 


OLORUA. 


Totoya. 


Plates 19*, Figs 4-7, and Plates 23, 66-69. 


Before entering the western passage through the outer reef surround- 
ing Totoya, we steamed round the eastern and northern edges of the 
outer reef to obtain a good idea of this interesting island. Totoya 
(Plate 23) is triangular in shape, enclosing an inner basin, nearly circu- 
lar, of three miles in diameter, and with a greatest depth of 35 fathoms. 
The width of the rim varies from two miles to a low narrow isthmus 
on the western face (Plate 66), the highest points of the rim being 
1,200 feet above sealevel. The eastern part of the rim is the broadest 
and highest. The basin is open to the south (Plate 67), the horns of 
the rim being about two miles distant. Stretching across this opening is 
the extension of the outer reef, which connects at the extremities of the 


BASIN OF TOTOYA CRATER, FROM THE SUMMIT OF THE NORTHERN RIM. 


rim with the narrow fringing reef bordering the island. Between the edge 
of the fringing reef on the western horn and the outer reef there is a nar- 
row but deep passage called the “ Gullet”’ (25 fathoms), affording a good 
entrance into the basin filling the extinct crater of Totoya, in which we 
anchored close to the inner edge of the northern part of the rim. The 
outer reef extends unbroken from the entrance on the west side to its 


38 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


northeastern extremity ; it follows irregularly the outline of the shore at 
a distance varying from one to over two miles. The outer reef off the 
north coast is broken into distant patches, leaving broad passages between 
them. North of the western passage the reef is also interrupted, leaving 
a boat passage. The outer reef flats are irregularly trapezoidal in out- 
line, and quite narrow. The greatest depth in the outer lagoon is 27 
fathoms. The eastern arm, and also the northern horn of the lagoon 
and the inner edge of the southern face of the outer reef, are studded 
with rocks and coral patches. The corals on the reef flats are thriving, 
and those on the patches inside of the lagoon are everywhere most flour- 
ishing. Many of the patches close to the outer shore line are in the 
extension of lateral spurs which have been eroded from the ridge of the 
rim. The general depth of the outer lagoon is over 20 fathoms along 
its central channel. Similar spurs run into the inner basin, and have 
formed extensive spits on which corals flourish, or islets and islands such 
as those figured on Plate 69, near the inner edge of the northern rim of 
Totoya. Near the centre of the basin there is an extensive coral patch, 
Kini Kini (Plate 23), formed upon the sides of a small islet rising from 
the bottom of the crater, as is so often the case in the craters of other 
volcanoes (see Plate 71). The volcanic rocks forming its centre are 
exposed at low water. The outer rim of the crater of Totoya has a 
diameter of six miles; it slopes quite evenly from the crest of the ridge 
to the outer and inner shore line; the slopes are cut by compara- 
tively shallow valleys, separated by ridges with rounded crests. (Plates 
67, 69.) 

The water which pours into the inner basin over the barrier stretching 
across the horns of the crater finds its only outlet through the ‘‘ Gullet,” 
where it rushes through with considerable velocity. The scouring effect 
of the waters rushing out of lagoons has been noticed by all who have 
navigated among coral reefs, and the strong currents flowing out of the 
lagoons through the encircling reefs of openings are constantly referred 
to in the sailing directions. 

In the extension of the western horn of the crater on the west of the 
“Gullet,” are two small islets (Plate 68), the remnants of a part of the 
southern rim of the crater. Small islets also exist off the west coast, on 
the northern side of the isthmus. They are remnants of one of the 
spurs putting out from the west side of the outer rim. From what we 
have seen in Totoya, there is little doubt that the fringing reefs, the 
shore flats, the coral patches, and in different parts of the lagoon the outer 
reef flats are the remants of flats formed by the denudation and subma- 


: 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 39 


rine erosion from the former extension of the slopes of the rim or of its 
spurs. These have been more or less connected together by the subse- 
quent growth of the corals which have found a footing upon them. 
Kini Kini and the other islets about Totoya, as well as the negro-heads 
on the reef flats and patches, all show the volcanic substructure upon 
which has grown and is thriving now a thin crust of corals. 


TOTOYA FROM THE NORTHEAST, DISTANT FIVE MILES. 


It has been difficult to explain the great depth in some of the lagoons 
of some atolls (60 fathoms). It seems to me that the conditions occur- 
ring in an island like Totoya give us a simple explanation of what such 
depths mean in coral districts situated in volcanic regions. Provided 
that we assume that these lagoons are in a region of elevation, as are the 
Fiji Islands, and that its volcanic peaks or ridges and volcanoes have 
been denuded and eroded, and that nothing has been left to indicate 
their former existence beyond the reef flats upon which the corals of the 
present day are growing. Remembering also that the corals can form 
but an insignificant crust upon the slopes and flats which have been pre- 
pared for their growth by the processes of elevation and of subsequent 
erosion and denudation, and that the features characteristic of the 
existing state of things was not brought about by the growth of the 
coral reefs of to-day except in a very secondary manner. We are not 
discussing the question of the formation of great limestone banks by 
subsidence to attain the proper depth at which corals may begin to grow. 
We are only trying to give an explanation of the conditions which must 
have preceded and have led to the existing state of things. 

The deepest water in the crater basin of Totoya is thirty-five fathoms, 
and it certainly cannot be held that a lagoon of such a depth has been 
formed by subsidence after the coral reefs have begun to grow. Let 
us now follow what would have become of Totoya had the denudation 
and submarine erosion which have brought it to its present state been 
continued during alonger period of time. A very few fathoms more, and 
we should have the rim divided into three large islands,—an eastern 


40 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


island with a ridge having a height of about 1,100 feet, a western island 
with a height of about 800 feet, and a northwestern island with a sum- 
mit of the same height. These islands might thus be reduced to three 
separate ridges, giving no indication that they had formed part of the 
rim of the crater of an extinct volcano. 

The denudation and erosion could be carried still further, leaving only 
islets, the summits of the higher peaks, to indicate the former position 
of the rim, the islets being joined by coral patches connecting their 
extremities, much as the present opening between the horns of the rim 
of the crater is closed by the outer reef. We may still further imagine 
it to be so far cut down as to form reef flats upon which coral would 
grow, thus forming a nearly circular atoll with a depth of 35 fathoms, 
— an atoll with the formation of which subsidence has had nothing to 
do. But this is not an imaginary atoll I am reconstructing. A number 
of such atolls are found in Fiji, the formation of which can be satisfactorily 
explained on the theory that the ring of coral patches represents the 
rim of an extinct volcano which has been cut away to below low water 
mark. Such atolls in the Fijis are probably Thakau Momo, Thakau 
Lasemarawa, Thakau Lekaleka, Motua Levu, Motua lai lai, Pitman 
and Williamson Reefs, and perhaps others. 

The example of Thombia, one of the Ringgold Islands, in which there 
is only a distant outer reef, would also indicate the possibility of the rim 
of the crater of a small volcanic peak cut down to the surface and forming 
the circular flats upon which corals might grow. In the case of Thom- 
bia such a condition would result in forming a diminutive atoll not more 
than a third of a mile in diameter, enclosed within an encircling barrier 
reef. 

We might also consider the “ Boilers,” the diminutive ‘ Serpuline 
atolls” inside of the lagoon of the outer reef off the south shore of the 
main island of the Bermudas,! as a series of such interior atolls, though 
the mode of origin is very different from that of subordinate atolls, 
formed, as I have suggested, upon the rim of an extinct crater like 
Thombia. In either case, the explanation of the formation of such 
interior or subordinate atolls is radically different from that given by 
Darwin? for their growth in the Maldive atolls, an explanation also 
accepted by Dana. 

It is becoming more and more apparent that each locality must be 


1 Bull. Mus, Comp. Zool., XXVI. No. 2, 1895, Plates XXII.-XXVL., p. 253 
2 Darwin’s Coral Reefs, 3d ed., p. 44. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 41 


considered by itself, and that no sweeping generalization can take in 
the formation of all coral reefs. Such atolls as those of Alacran on the 
Yucatan Bank of the Hogsty Reef in the Bahamas owe their origin — 
I mean the conditions existing there now — to entirely different causes 
from those which have brought about the formation of some of the atolls 
of Fiji, and the atolls of Alacran and of Hogsty themselves again owe 
their origin to different causes. The barrier reef of Florida does not 
owe its origin to the same causes as those which have led to the forma- 
tion of the Great Barrier Reef of Australia, or the barrier and fringing 
reef surrounding parts of Viti Levu, or some of the other islands of the 
Fiji group. 

It is playing with words to call such atolls as I have mentioned above 
pseudo atolls, as is becoming the fashion, and to speak of the localities 
to which Darwin’s theory of the formation of barrier reefs and of atolls 
does not apply as exceptions to the rule. These exceptions now cover a 
. good deal of ground. They include nearly all the coral reefs which 
have been examined by recent investigators,—from Semper in the 
Pelew Islands, Rein in the Bermudas, Murray in Tahiti and elsewhere, 
of Forbes, and of Bourne, of Guppy in the Solomon Islands, Kramer in 
Samoa, and others, —down to my own in Florida, the Yucatan Bank, 
Cuba, Bermuda, the Bahamas, and the West India Islands, as well as in 
the Galapagos and Sandwich Islands, besides the exploration of the 
Great Barrier Reef of Australia, and of the Fiji Islands. Surely the list 
of investigators and of localities is long enough. The negative evidence 
is now becoming overwhelming, and the recent borings at Funafuti have 
not weakened the position of those who do not recognize the Darwinian 
theory as of universal application, and as not having been proved to 
exist in a single instance, either by a careful examination of the locality 
or by borings. 


Taviuni. 
Plates 4, 18, 60. 


The islands of Taviuni (Plates 4, 18) and of Kandayu (Plates 10, 11) 
illustrate admirably the formation of reefs encircling denuded and eroded 
extremities of large islands, and readily explain the existence of very 
irregularly shaped reefs representing the former outline of the islands 
which they replace. Other characteristic points similar in their origin 
are the great spits forming the Namena Barrier Reef, which connects 
with the extensive reef platforms reaching towards Ovalau from the 
southeastern extremity of Vanua Levu (Plates 3, 3°) and the north- 


42 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


eastern spit of Vanua Levu, which breaks up into Kioa and Rambe Islands 
and the reef-bound platform from which they rise (Plate 4). 

On the platform of submarine denudation and erosion Namena and 
Vatu i thake Islands, as well as a few isolated rocks on the western edge 
of the southeastern horn of the Vanua Levu Barrier Reef are the only 
remnants of the former southern extension of Vanua Levu. To the 
southeast of this must have existed a dumbbell-shaped island of consid- 
erable height, of which only the summits of Makongai and of Wakaya 
are left (Plate 3*). 

The island of Taviuni is, with the exception of the shore fringing the 
northern half of the island and of the point of reefs off Vuna Point, 
destitute of reefs. The island is about 23 miles long, from five to eight 
broad, sloping uniformly to the shores from the backbone of the island. 
This rises to a height of over 4,000 feet. The main ridge sends off a few 
spurs towards the northeastern face of the island. The fringing reef 
attains its greatest width to the east of Naiselesele Point. It encloses 
a few small volcanic islets, varying in height from 60 to 90 feet, and the 
somewhat larger island of Mbuimbani (Plate 60), lying to the south, and 
which rises to a height of more than 400 feet. To the south the fringing 
reef becomes again quite narrow, and disappears at Laveine Point. 

Immediately north of Somo Somo Strait the submarine platform 
widens. Koro Levu Islet and Phillips and McPherson Rocks are in- 
cluded within shallow soundings covered with reef patches running out 
from the west shore of Taviuni. At a somewhat greater distance from 
the west shore of Tavinni within the 50 fathom line are Champion, 
Breaknot, and Maté Rocks, and to the northeast of Naiselesele Point the 
submarine platform reaches its greatest width, the Gangway Rocks and 
the bank connected with them being the most distant of the outliers of 
Taviuni. 

To the eastward of Taviuni lie the islands of Ngamia, Lauthala, and 
Matangi, separated from Taviuni by the Tasman Strait. The plateau 
from which these islands rise is really the extension of the shoal lying 
to the east of Taviuni and the outer reef which extends from Matangi 
east of Lauthala and south of Ngamia, stretching across Tasman Strait 
in disconnected patches and joining the fringing reef off Thurston 
Point. To the westward of Matangi the outer reef extends only in 
broken patches, and is seen also in the many disconnected patches found 
in the western part of Tasman Strait. Between Matangi and the 
northeastern horn of the outer reef there are two passages across it. 
The lagoon enclosing Ngamia and Lauthala has a greatest depth of forty 


‘ ae 
ee. Se ee 


——— 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 43 


fathoms and an average depth of over twenty, except to the east of 
Lauthala, where the outer reef joins the fringing reef which skirts 
Lauthala and Ngamia. There are a number of coral patches all through 
the lagoon, but they are most abundant along the inner edge of the 
southern line of the outer reef. 

Ngamia and Lauthala are both volcanic ; the former rises to a height 
of 1,000 feet. Both are indented with deep bays. 

Along the shore of Thurston Point we found a conglomerate in course 
of formation, composed of rounded pebbles of lava cemented together 
with broken fragments of coral. 


ELEVATED ISLANDS COMPOSED OF CORALLIFEROUS 
LIMESTONES. 


Negele Levu. 
Plates 17, 17°, Figs. 5-12, and Plates 95-99. 


Negele Levu is an elongated pear-shaped atoll, somewhat constricted 
at a few points (Plate 17). Its length is fourteen miles and its greatest 
breadth seven. The lagoon is enclosed by a continuous outer reef, 
varying in width from a quarter of a mile to over a mile. The western 
face of the outer reef is broken into patches leaving excellent deep 
passages for ships. The depth in the lagoon is quite uniform, the bot- 
tom being very level, varying in depth from about five to nine fathoms 
at the eastern extremity, and sloping very gradually to fifteen or sixteen 
at the western entrance. The bottom is composed of coralline alge, 
broken shells, and coral sand, as’ well as masses of dead corals derived 
from the disintegration of the former elevated coralliferous limestone 
which once covered the whole area of the lagoon. The lagoon is free 
from coral patches except at the eastern end, which is studded with 
heads of old coral and patches of living coral. These heads also form 
a belt of considerable width along the inner side of the outer reef flats. 

The reef flats are made up of elevated coralliferous rock which has 
been planed off to the level of the sea, and scooped ont below it to 
form the lagoon. At the southern of the western entrances there is a 
small sand key, and at the northeast end there are three islands, Ngele 
Levu, Tai ni Mbeka (Plate 96), and Taulalia (Plate 95). The outer 
faces of these islands form the sea face of the outer reef, there being no 
outside reef flats. These islands are entirely composed of elevated 


44 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


coralliferous limestones, rising on Ngele Levu to about sixty feet, on Tai 
ni Mbeka to forty feet, and on Taulalia to thirty feet. The process of 
disintegration which has taken place can still be seen going on at the 
extremities of the island of Ngele Levu. On the reef flat near it, as 
well as along the inner beach, crop out many negro-heads of elevated 
limestone rock, and between the smaller islands, which are now only 
connected by a reef flat, the islands themselves being undercut and their 


TAULALIA, NGELE LEVU LAGOON. 


surface deeply pitted and honeycombed (Plates 95, 96). On Taulalia 
many large domes of harder material, somewhat conical, still exist, 
which have not been rounded off to the general level of the island. 

We walked a good part of the length of the island of Ngele Levu, 
and crossed it at right angles. The elevated tertiary limestome rock 
was found cropping ont at all points (Plate 97), and towards the north- 
eastern shore we came upon a helt of limestone nearly devoid of vege- 
tation, which must have risen at points to fully sixty feet above the 
shore line. The surface of that part of the island was full of deep 
potholes and crevasses of all sizes and shapes, separated by ridges and 
columnar or conical masses, some of them fully fifteen feet alove the 
general level of the surrounding area (Plate 98). The rock surface in 
all directions was pitted and honeycombed, and eroded into thousands 
of sharp points and needles, the aspect of this island recalling a similar 
structure so common among the Bahamas. At Observatory Point, the 
southern extremity of the island, this very characteristic structure is 
quite well marked, and shows admirably the gradual passage of an island 
composed of elevated limestone rock into a reef flat identical in all 
respects with the reef flats surrounding the lagoon. Plate 99 shows the 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 45 


characteristic shore vegetation along the narrow cultivated strip of the 
island, while Plates 97 and 98 show the inland vegetation. 

We found rather distant coral patches growing in the lagoon in from 
six to seven fathoms of water, close up to the inner edge of the outer 
reef, starting from an underlying base of tertiary limestones, fragments 
of which we brought up with the dredge. And upon the plane of the 
outer rim of the lagoon, composed of the same tertiary limestones, corals 
were growing to a depth of from six to ten fathoms, or more perhaps. 


Wailangilala. 


Plates 18, 109, 110. 


The island of Wailangilala is somewhat triangular, and connected 
by a spit of coral beach rock with the small island of Cakandrovi to 


Copied from a Survey 
by Cap. B.Cocks. 


CAKANDROVI 


: Ree 


a. 
‘a Dry at L.WLor 4 Fide 


. 


$318v) 9 


the northeast. The east side of the larger island is about fifteen feet 
above high water mark. Both islands are low, with sandy or beach rock 


46 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


beaches, and covered with cocoanut trees and shrubs (Plate 110). The 
islands are in the northeast angle of a nearly elliptical lagoon (Plate 18), 
surrounded by a reef flat varying from a quarter of a mile to more than 


1mMie 
a a 


a mile in width. The outer reef is about nine miles in circumference. 
There is an entrance for ships into the lagoon in the western reef flats. 

The depth of the central part of the lagoon is from 22 to 23 fathoms, 
and the bottom is mainly coralline and coral sand, with broken shells. 
The inner edge of the reef flat is flanked by a broad belt of coral patches, 
which extend upon the flat itself, with here and there an isolated patch 
in six or seven fathoms of water. + 

Wailangilala was selected, after consultation with inhabitants of the 
Fijis well acquainted with the group, as affording an isolated atoll with 
a steep submarine slope, and an island on the outer rim on which to 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. AT 


establish the boring plant. Having a lighthouse on it, with a keeper 
and assistants, it afforded unusual facilities for establishing a comfortable 
camp for the boring crew, who were at work a couple of days after 
landing. 
The following is the record of our boring at Wailangilala.? 
From the surface — 
To 20 feet, coral and coralline sand with broken shells, like that on 
the beach. 
20-30 feet, coralline sand. 
30-40 ‘* coral and coralline sand, coarse. 
40-50 “fine coralline sand. 
49-51 “ parts of core of yellow limestone (elev. limestone). 


51-61 6“ “é 6c 66 “ ‘6 “ 
MIval 6c (74 6s “cc “ec “e “ 
Tapas (yy vee “ ‘“ 66 “ “c << 
80-85 oe (73 (73 “é “ ““ “<c 


It was on the western inner edge of the island (Plate 109) that I 
established our boring apparatus, soon after arriving at Suva, and while 
under the impression conveyed by the newspapers, and from published 
reports, that the second Funafuti boring expedition had demonstrated 
that at the Funafuti atoll true coral reefs extended to a depth of 643 
feet. This information seemed so positive that had it been received before 
the shipping of my outfit to Fiji via Australia, | should have remained 
at home, convinced that at any rate, whatever had been my experience in 
the West Indies, Australia, and the Sandwich Island reefs, yet that in 
a region of typical atolls in the Pacific the conditions of subsidence 
suggested by Darwin and Dana might exist, unless the boring at Funa- 
futi proved eventually, on closer examination, to have been carried on in 
the sea face talus of a reef. -But my outfit having left, I was not 
prepared to accept the preliminary conclusions of Professor David as 
recorded by the papers, and I started on my expedition ready to con- 
firm by my own borings the truth of the great thickness of modern 
coral reefs in atolls of the Pacific, or to give some other explanation 
of this apparently overwhelming proof of the correctness of Dar- 
win’s theory. 

From what we saw of the elevated coralliferous limestone at Ngele 
Levu, Vanua Mbalavu, Mango, and other points in Lau on our way to 
Ongea, it was very evident that these limestones attained a great thick- 


1 The bore hole was about five feet above high water mark, and about thirty 
feet from the shore line, a few feet north of the Landing (figure on page 45). 


48 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


ness, — 800 feet at Tuvutha, 1,000 feet at Vatu Vara. Therefore as 
soon as the drill struck the limestones it might correspond to any 
height in the beds exposed elsewhere, beds which at Mango, Kambara, 
and Vanua Mbalavu we had observed to rest upon a volcanic substratum. 
It was natural that immediately on my return to Suva after our first 
trip round the Eastern Archipelago I should send to Wailangilala or- 
ders to stop further boring, and to bring the crew and machinery back 
to Suva. For it seemed a waste of both time and money to bore and 
obtain a core from an indefinite datum plane, when the same evidence 
could be obtained by the examination of any one of the bluffs of ele- 
vated coralliferous limestones with which we had become familiar in our 
first trip. But, unfortunately, we were not equipped to make a thorough 
exploration of such a section, not being provided with explosives or 
drills, and had to content ourselves with somewhat fragmentary collec- 
tions at the more accessible points. However, this is a subject which 
I hope to attack again under more favorable conditions. 

The boring at Wailangilala shows that the island is the fragment of 
an ancient island of larger size, which once covered the whole area of the 
lagoon. Being at the northern extremity of the atoll, it was less subject 
to the destructive agency of the sea due to the prevailing southeasterly 
winds, and thus there was left a wider reef flat, the last to be worn 
away by the action of the sea. It also shows that at a depth of forty 
feet we meet the underlying elevated limestone forming the substratum 
of the northern reef flat of the lagoon. As will be noticed from the 
Figure on page 46, the western reef flat is much narrower than the 
eastern and less exposed face of the lagoon. 

The boring at Wailangilala is from the remains of an upheaved coral 
island, as has been suggested by Gardiner ;* but it is also the remnant 
of an island which once occupied the whole of that part of the atoll. 
Aiwa shows a stage antecedent to that of Wailangilala, the island on the 
rim of the lagoon being still of considerable height. Many of the reef 
rocks (negro-heads), which Gardiner considers as having been thrown up 
by hurricanes, are the remnants of the elevated reef-rock outliers left 
from the denudation of the flats on which they oceur, and which once 
rose to a greater height but have gradually been eroded and planed down 
to their present elevation. 

But Gardiner is wrong in assuming that the islands of the atolls are 
converted into land. Such is by no means necessarily the case. The 
islands on the rim of an atoll, as Ngele Levu, consist of elevated coral- 


1 Loe. cit., p. 445. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 49 


liferous limestone rock, and are the remnants of the former land mass 
once covering the area of the atoll of Ngele Levu. 


Nuku Mbasanga. 
Plates 18, 22%, Fig. 18, and Plate 108. 


We skirted along a part of the southwestern edge of Nuku Mbasanga 
atoll (Plate 18). The atoll is oblong, a little over two miles long, open 
to the northwest, where the reef flats are broken up into numerous 
coral heads. Within the broad reef flats are a small sandy cay, Nuku 
Mbalate on the western face of the atoll, and the islet of Nuku Mbasanga 
(Plate 108), the shores of which are covered with coral beach rock, or 
patches of elevated reef rock, judging from the character of the negro- 
heads which crop out on the western side. Both the islands are covered 
with coacoanuts and shrubs. 

There is every reason to believe that the islands of the Nuku Mba- 
sanga group are the remnants of an island composed of elevated lime- 
stone, which has been denuded and eroded to its present condition, and 
partly covered, as Wailangilala has been, with coral sand. 


Nukusemanu and Nanuku Reefs. 
Plates 18, 103-107. 


To the eastward of Budd Reef, and separated from it by a channel 
about nine miles wide, is situated an elongated, angular, irregularly 
shaped atoll, terminating at its southern extremity in a long ridge of 
reef flats called the Nanuku Reef. These send out spurs, the extension 
of which connects with the Nukusemanu Reef and encloses a lagoon 
fully twenty-four miles long and from two to six miles broad. The 
greater part of the eastern face of the reef is not awash, being made up 
of a long series of coral reef patches, with from one to six fathoms of 
water, with deeper water between it and the extension of the Nanuku 
Reef. A tongue of the ocean runs westward from 118 fathoms in the 
gap separating the extremities of the reefs, rising to a ridge with five 
to ten fathoms, separating it from a deep pool with as much as forty-six 
fathoms near the eastern face of the central part of the western reef flat 
of Nanuku Reef. Only an occasional reef patch rises to the surface on 
that face. On the northeast horv is situated Nukusemanu Island, a 
small sand key covered with cocoanuts. On the northwest face the 
Nukusemanu Reef flats are seen to be well covered with flourishing coral 

VOL, XXXIII. 4 


50 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


patches, but nearly the whole of the west face until it joins the western 
spur of Nanuku Reef consists, like the east face, of a long but narrow 
reef flat, with from two to seven fathoms, and studded with heads. The 
greatest depth in the lagoon is 52 fathoms, with an average depth of 
from 25 to 40 fathoms. The interior of the lagoon, especially the 
northern part, is studded with heads. 

We examined the islets on the southern spits of the Nanuku Reef. 
The northern islet, Nanuku lai lai, has been nearly washed away during 
the hurricane of 1893 (Plate 107). The southern islet is covered with 
shrubs and cocoanuts (Plate 104). The eastern face of this islet, 
Nanuku Levu, is flanked with beach rock (Plate 106). There were a 
large number of negro-heads of beach rock and of elevated coralliferous 
rock scattered upon the reef flats adjoining the island (Plate 103), and 
both to the north and towards the southern extremity of the reef flat 
ridge (Plate 105). Coral heads begin at about seventeen fathoms off the 
lee side of the reef, the patches increase in size and number at twelve 
fathoms, and form a very fine flourishing belt between six to one and a 
half or two fathoms. We could trace these coral patches on the nar- 
row reef flat ridge exteuding northward. This ridge is at some points so 
narrow that the breakers form a long white mass of rollers as they fall 
from the windward to the leeward side of the reef flat. The leeward 
pitch is not as steep as the charts seem to indicate. We found a hun- 
dred fathoms on that side, hard bottom, at a distance of one and three 
quarters miles from the leeward edge of the reef flat, two and a quarter 
miles northerly from Nanuku lai lai (Plate 18). 

The island which once covered the tract extending from the northern- 
most horn of the Nukusemanu Reefs to the southwestern horn of the 
Nanuku Reefs (Plate 18) was probably flanked by outer ridges of hills 
running into a long narrow ridge at the southern extremity, of which 
Nanuku lai lai and Nanuku Levu islets are the solitary remnants, while 
Nukusemanu Island is the only fragment of the northern extremity of 
the eastern ridge. There must have been a valley separating the ridges 
now indicated by the open lagoon, with a greatest depth of over forty-five 
fathoms, extending from Nanuku Reef to Nukusemanu Reef, which was 
, cut into at many points all along the outer edges of the ridges, and con- 
nected the plateau of submarine erosion with the great sound of the 
interior. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 51 


Tuvutha. 
Plates 20, 88, 89. 


Tuvutha Island is triangular in shape ; its northern face is about one 
and three quarters miles long; the island is nearly three and a half 
miles long, and trends in a northwesterly direction from the southern 
point to the northern face (Plate 20). It is surrounded by a barrier 
reef. The greatest width of the enclosed lagoon is about three quarters 
of a mile on the eastern side ; it is somewhat narrower off the western 
face of the island. At two points on the northern side of the island the 
outer reef becomes a fringing reef for a short distance. There are a 
couple of boat passages into the lagoon through the outer reef flats, one 
on each side, The lagoon varies in depth from two to nine fathoms. 
With the exception of the central part of the eastern lagoon, it is 
studded with coral patches and negro-heads. The latter are especially 
numerous off the northern face of the island between those points 
where the outer reef becomes a fringing reef, and empounds a small 
distinct lagoon. 

The central ridge, occupying the interior of the northern part of the 
island, runs parallel to the west coast, and as far as I could judge con- 
sists of coralliferous limestone elevated to a height of eight hundred feet. 
The central ridge is surrounded by a more or Jess continuous ridge, form- 
ing an outer rim and surrounding the inner depressed part of the island. 
This ridge consists entirely of elevated limestones, forming along the 
northern face a collar of steep bluffs (Plate 88). Other parts of the 
ridge, especially on the west side of the island, have been greatly 
denuded and eroded into rounded peaks and domes, while the southeast 
point is marked for its steep bluffs and sharp ridges (Plate 89). Where 
the bluffs rise from the shore of the lagoon, they are deeply undereut. 
The outer ridge not being low and broken at any point, no interior 
lagoon or sound has been formed with the exception of a small bight on 
the southern part of the eastern face of the island (Plate 20). 

The central voleanic mass which has elevated Tuvuthd as well as 
Naiau has not broken through the elevated limestones, although it has 
assumed the appearance of the wide round rim of an extinct crater. 
But, as will be seen in the case of Naiau, the formation of the central 
basin is not due to volcanic agencies, but to atmospheric causes. 


52 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Naiau. 
Plates 20, 22°, Fig. 1. 

Naiau Island is, like Tuvutha, composed entirely of an elevated lime- 
stone ridge forming a continuous rim round a central depression stated 
to be about 200 feet lower than its highest points, which rise from 530 
to 580 feet above the level of the sea. The sea face of the rim rises 


NORTH POINT OF NAIAU. 


in nearly perpendicular bluffs round the island. At their base they are 
deeply undercut, and the larger fragments are eroded into dome-like 
heads. Off the southeastern point an islet has been isolated from the 
island. Naiau is surrounded by a fringing reef broadest on the eastern 
face, about half a mile wide, where at half tide boats can pass between 
it and the shore, forming an incipient lagoon, and enter through a 
narrow boat harbor passage, out of which, [ am informed by our pilot, 
runs a strong current. There are numerous negro-heads all along the 
outer edge of the fringing reef, especially near the northwestern point of 
the island, where the fringing reef is narrowest. 

Naiau,? Tuvuthé, Kambara, Wangava, and other elevated islands, 
consisting of coralliferous limestone, have been considered to be elevated 


NAIAU, SEEN FROM THE EAST. 


atolls, owing to the existence of a depression in the summit, which is 
looked upon as representing the former lagoon. While that may be the 


1 Moore, Nature, March 18, 1897, p. 463. Others have looked upon these islands 
as extinct craters. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 53 


case, I am inclined to consider these central basins as due to the action 
of atmospheric agencies, and to look upon them as similar to the gigantic 
banana holes, as they are called, occurring in the Bahamas, which are 
undoubtedly due to the solvent action of the rains overcharged with car- 
bonic acid, which carry off the limestones, and, percolating through the 
mass, leave the saucer-shaped basins characteristic of the so called ele- 
vated atolls. In such islands as Naiau, Vanua Vatu, Tuvuthaé, Kambara, 
and Wangava, the central depression has not extended very far towards 
the sealevel. But. in such islands as Mango the central depression has 
formed a small lagoon, in Namuka submarine erosion has carried off one 
side of the rim; in Fulanga (Plate 22) the process has been carried 
still further by the direct action of the sea and of submarine erosion, 
forming a large lagoon; and the conditions existing at Ongea, Yangasa, 
Aiwa, and finally at Reid Haven, Wailangilala, Ngele Levu, etc., illus- 
trate the different stages in the transformation by submarine erosion of a 
so called elevated atoll of tertiary age into an atoll of the present epoch. 
The probable extent to which atmospheric agencies have contributed 
to shape such central basins is also shown from the presence of exten- 
sive caves in the elevated limestone islands of Vatu Leile, of Thithia, 
and of Ngillangillah, and in the numerous cracks, caverns, and cavities 
which characterize the faces of the vertical bluffs of elevated limestone 
wherever we have met them in the Fijis (see Plates 74, 77, 92). 


VATU VARA, SEEN FROM THE EAST. 


Vatu Vara. 
Plate 19. 
On the last trip of the “ Yaralla” from Suva to Wailangilala, Captain 
Thomson examined for me the islands of Vatu Vara, Yathata, Kaimbo, 
and Naitamba. The accompanying account is based upon his notes. 


54 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Vatu Vara or Hat Island (Plate 19) is one mile and a quarter in 
diameter. Its summit is flat, and falls off on all sides in steep cliffs. 
It attains an altitude of 1,050 feet. The cliffs consist of elevated lime- 
stone standing out conspicuously through the dark foliage which covers 
the island from base to summit. Up to the very summit of the island 
the exposed rocks are seen to consist of limestone. The island is 
surrounded by a fringing reef nearly a mile in width on the west coast. 
On the east and north sides the sea breaks against the nearly vertical 
limestone cliffs. They are deeply undercut. On the northwest side two 
separate masses of limestone stand out midway between the base of the 
cliffs and the outer edge of the reef. An incipient lagoon, open to the 
north, is forming along a part of the west coast of the island. 


Yathata and Kaimbo. 


Plate 19. 


The islands of Yathata and Kaimbo (Plate 19), which rise respectively 
to the height of 840 and 150 feet, are composed of elevated limestone 
rock. A fringing reef encloses them both. It attains a width of over 
half a mile where it connects the islands, and is nearly a mile wide 
off the north of Yathata. Off that shore a number of small islets and 
heads stand out between the island and the outer edge of the reef. Else- 
where the fringing reef is narrow. Between the islands in the middle of 
the fringing reef stands out the islet of Nuku Levn, 90 feet in height, 
and a few heads. There appears to have been a secondary elevation on 
the south side of Kaimbo, where the undercut ledge has been raised about 
twenty feet above high water mark. 

Iam informed by Captain R. Cocks that Katavanga is composed of 
elevated limestones. 


Aiwa. 
Plates 21, 22°, Figs. 13-15. 


Aiwa consists of two small elongated islands, the western one of which 
is not quite a mile in length (Plate 21). Both are composed of elevated 
limestone, pitted and honeycombed, forming low vertical bluffs along 
their southern faces. The highest points of the islands are respectively 
210 and 200 feet. They are connected by a coral reef awash at low 
tide. The islands are in the middle of the southern face of the outer 
reef flat, which encloses an elongate narrow triangular lagoon nine miles 


: 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. EE, 


inlength. From the extremities of the islands off the south face projects 
a horn of the outer reef, forming a small enclosed lagoon separated from 
the principal lagoon and with a greatest depth of ten fathoms. The 
greatest depth of the principal lagoon is 23 fathoms. The northern face 
of the outer reef is much broken, and flanked by large patches of corals 
and heads, with a wide entrance into the northwestern end of the lagoon. 
The western face of the lagoon is three miles long. The inner edge of 
the western face is flanked by a broad belt of coral patches and heads. 
The coral patches are growing upon sunken heads of elevated reef rock, 
the remnants of the elevated reef once covering the area now occupied 
by the Aiwa lagoon. The reef flats consisted wherever we saw them of 
elevated reef rock planed off to a general level, upon which coral patches 
were growing. 

This group is historically interesting, as Dana in his Corals and Coral 
Islands (p. 264) gives a section across the islands and lagoon, which 
according to him illustrates very forcibly the effect of subsidence in 
the formation of -atolls. A more unfortunate selection could not have 
been made. But Dana did not visit this group, and took his information 
from the charts, or he would not have chosen as an illustration an island 
group which consists of elevated limestone rock,— islands which after 
their elevation have suffered most extensive denudation and erosion, and 

upon the outer edge of the surrounding platform the corals of the present 

epoch have found a footing and formed a sheet of very moderate thick- 
ness. The lagoon between the encircling reef and the islands has 
been hollowed out by mechanical causes similar to those which I have 
alluded to elsewhere, and which have in my opinion shaped the lagoons 
of all the atolls and barrier reefs of the Fijis. 

Dana assumes the lagoon of Aiwa to have been formed during the 
slow subsidence of the island enclosed within its reef, while there is every 
evidence that the lagoon of Aiwa has been scooped out by submarine 
erosion, and the island, consisting of late tertiary limestones, has been 
lowered by denudation, and that the limestones after their elevation have 
remained at the present level, and that the corals now growing upon the 
outer rim and upon the reef flats, as well as the coral heads inside of the 
lagoon, have but little thickness, and that well within the greatest depth 
at which reef-building corals can grow. 


56 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


Oneata. 


Plates 21, 22%, Figs. 10-12. 


Oneata Island is a low ridge of elevated limestone, rising to a height 
of 160 feet, connected at its eastern extremity by a coral reef with the 
islet of Loa, of similar structure to Oneata, and rising to a height of 
140 feet. Towards the eastern extremity of Oneata, on the northern 
side, the island is indented by deep bays, studded with mushroom- 
shaped islets and large heads barely cropping to the surface. The spit 


ONEATA. 


protecting the bay from the east rises vertically, is deeply pitted, full of 
potholes, and honeycombed and perforated by a large opening similar 
to the Hole in the Wall at Abaco in the Bahamas. Everywhere on the 
surface of the island we found 
the elevated limestone cropping 
out. The southern face of the 
island is also indented with 
bays, the beginning of shallow 
sounds which are now cutting 
Oneata into smaller islands by 
undermining the shore line and 
forming low vertical cliffs, prob- 
ably by the same processes which ISLET OFF ONEATA SHORE. 
disintegrated the area formerly 

occupied by the elevated limestones, and of which Oneata and Loa are 


the remnants. : 
Oneata lies about a mile from the inner edge of the outer reef flat, 


~ aaaiins 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 5ST 


enclosing a triangularly shaped lagoon, with a greatest depth of 21 
fathoms. The length of the southern reef flat is a little over ten miles, 
that of the northern face about nine miles, and that of the western and 
northwestern faces connecting them is five miles. There are three pas- 
sages on the western and northwestern faces, and one through the north- 
ern face. The bottom of the lagoon, between the reef patches and heads, 
is covered with coralline alge and with coral sand. There are many 
large heads scattered along the inner edge of the northern reef flat, and 
on the extension of the western extremity of the island. 


Namuka. 


Plate 22. 


We did not visit Namuka, but steamed near enough to the island to 
recognize its distinctive features. It is a narrow, undulating ridge, four 
miles long, rising to a height of 240 feet; it is composed of elevated 
limestone. On the southern and western faces there are deep bays, or 
incipient sounds, which, if extended, would divide the island into a 
number of islets. The island is surrounded by a fringing reef off the 
southwestern extremity, and off the eastern point of the island. Be- 
tween these points an outer reef extends off the south coast, forming a 
narrow and shallow lagoon full of heads, with five fathoms at its deepest 
point. On the northern face the western part of the lagoon is deeper, 
having thirteen fathoms. The horns of the outer reef of the northern 
and western faces are connected by broken patches and heads which 
form the harbor of Namuka. 

About three and a half miles northeast from the entrance to Namuka 
Harbor lies Wilkes Reef (Plate 22), a flat a little over halfa mile in 
length, dry at low water, with cutlying rocks and banks within the sur- 
rounding 100 fathom line. 


Yangasa. 


Plates 22, 22°, Figs. 8, 9, and Plates 90-93. 


The cluster of Yangas4 (Plate 22) consists of four islands and numer- 
ous rocks and islets, all of which are composed of elevated limestone. 
The largest island of the group, Yangasé Levu, is nearly two miles in 
length and about half a mile wide. Its shores are formed of precipitous 
cliffs, which surround the whole island ; they are deeply undercut at the 
base, perhaps more than any other island we have seen in Fiji. The 


58 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY, 


crest of the highest ridge is flat, and runs ata general level of about 
300 feet. The highest summit, toward the southern end of the island, 
is nearly 400 feet ; off that point there are indications of a terrace at 
about one third the height of the island, as if the elevation of this 
group had taken place at two successive periods. Yangasé Levu seen 
from the west, on the way to Ongea, appears hat-shaped, with a high 
terrace forming the rim. The island of Yangasé Levu is from one to 
two miles distant from the inner edge of the outer reef flat forming the 
eastern horn of the lagoon. Along the western side of the lagoon are 


== a = al 
——$— SSS ae ae 


YANGASA LEVU. 


situated Navutuira, in the northwest angle of the lagoon, which rises to 
270 feet ; this is connected with the islet of Yuvutha (Plate 90) by a 
long narrow reef studded with mushroom-shaped rocks rising above 
high water mark. The whole of the northwestern part of the lagoon 
to the west of the ship passage on the north face of the outer reef flat is 
also thickly studded with negro-heads and with mushroom-shaped rocks 
_ of all sizes and shapes, which cover the wide reef flat to the west and 
north of Navutuira. The: large mushroom-shaped heads are generally 
on the extension of spits or headlands of the two islands named. 

The crest of Navutuira is undulating, and from its shores rise low 
undercut vertical bluffs. Yuvutha (Plate 90), on the contrary, has a 
conical outline, its highest summit rising to 240 feet ; its vertical shore 
bluffs are higher than those of Navutuira, deeply undercut ; they are 
nothing but the rim of a sound left from the disintegration, denudation, 
and erosion of the adjoining land. Such rims are at a distance readily 
mistaken for the rims of extinct craters. We anchored off the west side 
of Navutuiloma, the most southern of the islands along the west side of 
the lagoon. The small bay on the north face of Navutuiloma resembles 
closely a part of the rim of an extinct crater. But that rim and those 
forming the eastern and western points are entirely composed of ele- 
vated limestone, full of caverns and caves, pits and potholes, many of 
them full of red earth, as is the case wherever elevated limestone is 
met with; it is deeply honeycombed and cut into ridges (Plate 92), 
upon the edges of which rise endless sharp pinnacles and needles. 
This was also the structure and appearance of the inland slope of 
the island where we landed. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 59 


The little bay was studded with mushroom-shaped and conical islets 
and rocks, all deeply undercut (Plates 91, 93), and the bottom in from 
two to four fathoms was covered with sunken coral patches and heads 
rising at all depths. 

Some of the islets were covered with bushes and cocoanut trees, like 
the main island. The highest point of Navutuiloma is 210 feet; it is a 
little over one mile in length, and is larger than Navutuira. The shape 
of the outer reef flats enclosing the lagoon of Yangasa (Plate 22) is ir- 
regularly rectangular, with rounded angles; the faces are each about 
five miles long, the western face being the longer. On the eastern and 
northeastern side, the reef flat is quite narrow, but it is studded along 
the inner edge with a belt of heads and coral patches and negro-heads. 
Off the southeastern horn, the reef flat becomes very wide, projecting in 
a point fully two miles beyond its general line. The reef flats of the 
southern and western faces are also broad, fully a mile in width in some 
places, and at the northwestern horn the reef flat is more than a mile 
and a quarter wide. , 

On the northern face of the lagoon a tongue of deep water (145 fath- 
oms) fully a mile wide runs towards the centre of the lagoon ; this is the 
passage used for entering the lagoon. The slope of this part of the lagoon 
is very steep, and it is studded with coral patches and heads growing 
upon the remnants of the former island of Yangasé. This narrow and 
deep tongue of the ocean represents probably an original valley formed 
in the uplifting of the island, and has no connection with a subsidence 
of the island during the formation of the encircling reef, which has 
grown subsequently upon the platform of submarine erosion formed by 
the wearing away of the original land mass. The average depth of the 
northern part of the lagoon is from 14 to 19 fathoms. The southern 
part, between Yangasé Levu and Navutuiloma and the reef flat, is shal- 
lower, from six to twelve fathoms, with a still shallower belt along the 
inner edge of the southern reef flat. 

Off the southeastern extremity of Navutuiloma extend a number of 
mushroom-shaped rocks and islets, deeply undercut and eroded into fan- 
tastic crests, pinnacles, and summits. The reef flat of the western face 
of the Yangas4 lagoon is full of thriving coral patches, which extend 
along the inner edge, between and upon the negro-heads, down to seven 
or eight fathoms. The formation, by erosion and denudation, of diminu- 
tive or incipient sounds, as in the bay of Navutuiloma, is interesting as 
representing one stage in the action of such processes, of which others 
can be followed in the conditions which have been reached by such 


60 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


islands as Namuka, Mango, Ngele Levu, Fulanga, Oneata, Ongea, and 
others. It is quite probable that the islands and islets of this group 
represent the remnants of the submarine erosion and denudation which 
have cut the greater island of Yangasa, consisting of elevated limestone, 
which once occupied the area of the lagoon, into smaller islands by a 
process similar to that now going on to cut up the island of Navutui- 
loma, —a process which has left, as indicating its former greater extent, 
the islands of the cluster, ‘its rocks and islets, and the numberless heads 
cropping out everywhere over the outer reef flats, and in the extension 
of the spits and points of its islands. 

To the eastward of the Yangasa cluster, and separated from it by a 
narrow channel of about half a mile in width and a depth of a little 
over 100 fathoms, lies Thakau Levu (Plate 22), an elongated horseshoe- 
shaped atoll, nearly four and a half miles in length, with a greatest 
breadth of less than two miles. The lagoon enclosed by the outer reef 
flat is open on the west face. The greatest depth in the lagoon is 11 
fathoms; it is studded with heads and patches. The reef flat at the 
eastern point of the lagoon is fully a mile wide. 

South of Thakau Levu (Plate 22) lies the flat reef of Thakau Thi- 
kondua, and the small island Naiabo, of elevated limestone, rising to a 
height of forty feet, surrounded by a narrow encircling reef enclosing 
a shallow lagoon. Still farther south are the flat reefs of Thakau Reiva- 
reiva and Thakau Nasokesoke, both, according to the sailing direc- 
tions, dry at low water and steep to all round. We did not visit either 
Thakau Levu or the last mentioned reefs. 


Ongea. 
Plates 22, 22°, Figs. 6, 7, and Plate 94. 


The Ongea group consists of two large islands, Ongea Levu and 
Ongea Ndriti, and numberless mushroom-shaped or conical or dome- 
shaped islets and rocks, studding both the passage between the two 
principal islands or fringing the shores or extending across the openings 
of the bays which indent the coast line of Ongea Levu and Ongea Ndriti 
(Plate 22). The larger island, Ongea Levu, runs nearly north and 
south ; it is four miles long, and varies from one to two miles in width ; 
it rises to a height of 270 feet. This island lies in the centre of the north- 
ern part of the lagoon, about equidistant from the outer encircling reef 
flats, within a channel from three quarters of a mile to a mile in width, 
and varying in depth from seven to twelve fathoms. Off the southern 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 61 


end of Ongea Levu the lagoon expands, and attains a width of nearly 
six miles. The outer reef flat is narrow, but expands to a width of 
three quarters of a mile off the southern face of Ongea Ndriti, where 
it becomes a fringing reef. Ongea Ndriti is nearly two miles long 
and one mile broad, and rises to a height of 300 feet. The Barracouta 
Passage is the only ship channel leading into the lagoon. It opens 
through the western reef flat into the widest part of the pear-shaped 
lagoon, a little south of the extremity of Ongea Levu. The greatest 
length of the lagoon is about eight miles. 

The Ongea Islands consist of elevated limestone, rising in nearly verti- 
cal cliffs along the shore line. This is deeply indented by broad and deep 
bays, forming small irregularly shaped sounds, which in the case of Ongea 
Levu have nearly cut that island into two (Plate 22). The openings of 
the bays and the shores of the islands themselves on the western and 


a N.W 


SOUTIIWEST POINT OF ONGEA LEVU. 


southern faces of Ongea Levu are studded with islets and rocks, which, 
like the ridges of the islands, consist of elevated limestone. They are 
most numerous off the wide and deep bay on the southern face of ihe 
larger island, and extend across the channel separating Ongea Levu and 
Ongea Ndriti (Plate 94). The outliers extending south from the former 
island connect with those stretching north from the opposite face of the 
smaller island. 

The mushroom-shaped rocks and islets also extend along the western 
face of Ongea Ndriti, but they are not as numerous as on the northern 
face. On many of the islets are found a few straggling palmettos, iden- 
tical with those growing on the principal island. The islets and rocks 
as well as the shore cliffs are deeply underent, and the surface is deeply 
pitted, honeycombed, and full of potholes and eaverns, and presenting 
the appearance so characteristic of the weathered coralliferous limestone 
wherever we have found it in Fiji. It seems, however, as if the erosion 


62 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


and denudation, and the accompanying weathering, had been more in- 
tense as we proceeded southward along the windward islands of Fiji. 
The islets and rocks remaining as evidence of the former connection of 
the islands of this group are perhaps as good illustrations as any we 
have seen of the process which has been going on to reduce to its present 
proportions the original reef flat or island, which probably once covered 
the whole of the area of the Ongea Lagoon. The bottom of the lagoon 
is made up of coral and coralline sand. Half a mile from the north- 
eastern horn of the outer reef of Ongea rises a sharp submarine peak, of 
which only the rock rising on the western edge remains, and on which 
has been formed the small circular reef of Thakau Teteika, about three 
quarters of a mile in diameter; while to the southeast, distant about 
three miles and a quarter, rises Nuku Songea, a triangularly shaped 
atoll enclosing a shallow lagoon with a low sand key at its northern 
extremity. 


Fulanga. 
Plates 22, 22%, Figs. 4, 5, and Plates S0-S4. 


Fulanga is an elliptical island deeply indented on its southwestern 
face (Plate 22), along which rises a ridge of elevated limestone to the 
height of 240 feet. This tertiary limestone rock has been elevated to a 
height of 260 feet at Quoin Hill, on the northeastern face of the island. 
The “ Sailing Directions” (p. 214) represent Fulanga as “ of voleanic and 


ENTRANCE TO FULANGA. 


coral formation, and the circular shape of the island leads to the suppo- 
sition that it is the rim of an extinct crater.” What I have seen of 
Fulanga shows no trace of voleanic rocks, though they may exist on the 
southwest shore, which we did not see. Mr. Gardiner,’ who visited 
Fulanga, classifies it among the limestone islands. It is quite natural 


1 Proc. Cambridge Phil. Soe., Vol. IX. Part VIII. p. 458 (1898). 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 63 


that the honeycombed pitted pinnacles of hard ringing limestone should 
be mistaken by inexperienced observers for volcanic clinker-like rocks, 
and the locality described as volcanic, especially when taken in connec- 
tion with the crater-like aspect of the sounds. The island is surronnded 
by a fringing reef nearly a mile in width in some places, and with a pas- 
sage forming a shallow and very narrow lagoon with a depth of four to 
five fathoms between the outer reef flat and the shore line along parts of 
the eastern and of the western face of the island. There is a narrow 
passage (Plate 82) on the northeastern face into the interior basin, but 
too shallow to have admitted the “ Yaralla.” In addition there are also 
a number of openings between the numerous islands and islets into 
which the elevated limestone ridge has been cut up (Plate 80). Through 


all these the current flows with considerable velocity (three knots). The 


EAST SIDE OF FULANGA. 


interior of the basin is full of islets and of rocks, mushroom-shaped or 
dome-shaped, all deeply undercut and all consisting of the same elevated 
limestone of which the outer ridges are composed (Plate 81). These 
islets and rocks are of all sizes and shapes, some of them nearly half a 
mile in length ; and they are found in every part of the basin (Plates 
83,84). The greatest depth of the interior basin is ten fathoms, with 
an average of five to six. 

Although the general appearance of Fulanga is much like that of an 
extinct crater, yet its formation is due to other than volcanic agencies. 
The whole of the area of Fulanga must formerly have been covered by 
a bed of raised coralliferous limestone. The lower parts of the eastern 
face of this elevated flat became cut up into islands and islets, allowing 
the passage of the sea, and it has little by little eaten into the body of the 
elevated limestone, forming an extensive inner basin four miles in length 


64 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


by two miles wide, leaving the basin studded with innumerable islets 
and rocks (Plates 83, 84) such as I have already mentioned. These 
islands have usually vertical faces; many of them are conical, dome- 
shaped, or mushroom-shaped, like the islands and islets inside of the 
interior basin. A similar process has been going on off the northern 
point of Fulanga, south of Quoin Hill, where the conical and dome- 
shaped and mushroom-shaped islands and islets and rocks are seen to 
pass gradually from conical or dome-shaped bluffs along the shore line 
into the negro-heads of the outer reef flat off that point. This process 
of disintegration must have been similar in every respect to that which 
has formed the sounds in the Bermudas, eating small bays into the 
faces of bluffs inland, these becoming circular with time, with only a 
narrow opening, and finally leaving merely a narrow ridge or parts of 
ridges surrounding a central basin resembling an atoll. 


FULANGA SOUTH OF QUOIN HILL. 


If the process which has been shaping Fulanga had been going on 
longer the result would have been a low ridge on the southwestern face 
of an elliptical outer reef flat, with an enclosed lagoon full of islets or 
rocks or heads, and here and there perhaps an island or islet indicating 
the former existence of the elevated coralliferous limestone ridge ; there 
being a passage into the lagoon where it now exists, the lagoon as en- 
larged including the true lagoon and the “ Sound ” basin, — a condition 
of things very similar to that found on Oneata, Ngele Levu, Yangasé, 
Nanuku, and on Vanua Mbalavu. On the faces of the islands and islets 
forming the eastern ridge of the basin of Fulanga rise vertical cliffs 
deeply undercut and weathered. The reef flats are full of negro-heads, 
some of which are of considerable size. The reef flats are everywhere 
covered with extensive stretches of flourishing corals. 

This atoll-like basin has thus in reality been formed by the wearing 
action of the sea, and subsidence has played no part in its formation; on 
the contrary, the coralliferous limestone flat covering the basin has been 


ete, an is 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 65 


elevated to nearly three hundred feet, and it has been subject for a long 
period to the action of the atmosphere and of the sea; the one wearing 
down the limestone land into an inner basin or cutting it out into 
valleys, and finally into islands and islets ; the other encroaching into it 
from the outside, and eventually forming an interior basin studded with 
islets, which to all appearance would be a lagoon surrounded by an 
encircling reef with its heads and patches and islands and islets. And 
yet it would really be a crater-like basin, a ‘‘ Sound,” which by erosion 
had become connected with the true barrier reef lagoon, and finally even 
all trace of the Sound character of the inner basin might vanish with 
the disappearance of the old shore line, and the existence of only islets 
to indicate the former land area. 

In the case of Fulanga, Gardiner? has well described the action of the 
sea both as a solvent and as a disintegrating factor in reducing the rocks 
and islets to mushroom-shaped structures, and in the great undercutting 
of the cliffs, of which he gives the same illustration as that I give here, 
which was kindly furnished me by the Hon. W. L. Allardyce. He says: 
“The final result should be a perfect atoll reef just awash, the land be- 
ing dissolved away while the living reef round it continues to grow.” 
So it does, but the reef has played no part in the shaping of the atoll, 
the lagoon of which owes its existence to the formation of the interior 
Sound by the decomposition of the elevated tertiary limestone reef mass, 
and has no connection with the recent coral reef growing upon the reef 
flats or external platform of submarine erosion. 


SOUTHEAST POINT OF MARAMBO. 


Marambo. 
Plate 22. 
-Marambo is a small circular island about three quarters of a mile in 
diameter (Plate 22). It is composed of elevated limestone rising to 
160 feet in height. It is surrounded by a fringing reef fully a mile in 


1 Loe. cit., p. 459. 
VOL. XXXIII. 5 


66 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


width off the northern extremity of the island. Off the southwest face 
of the island there is a shallow incipient lagoon. There is a large crack 
running through the peak of the highest point of the island near the 
southern point, as if the sea face might scale off at any moment and form 
a vertical cliff. There isa fine vertical cliff along the northeast point of 
the island over 100 feet in height, deeply undercut. From the lower 
edge of this cliff numberless negro-heads extend over the surface of 
the fringing reef flat, which is covered by large patches of flourishing 
corals. 


NORTH POINT OF MARAMBO. 


Dana and Darwin both speak of fissures passing through the shore 
shelf reef. The fissure we saw at Marambo I attribute to the giving 
way of the shore bluffs from the undermining preparatory to its shal- 
ing off. 


W angava. 
Plate 22. 


Wangava, as seen from the passage between it and the northern ex- 
tremity of Kambara, appears to be composed of two parallel ridges of 
limestone, elevated to a height of nearly 300 feet. The island is steep to 
on all sides, steep cliffs forming its eastern and western faces. It is 
surrounded by a wide fringing reef (Plate 22) except off the north face, 
where it becomes broken up into coral heads and patches. 


Vatu Leile. 
Plates 9, 17°, Figs. 1-4, and Plates 100-102. 
Vatu Leile, the westernmost island of the group we examined, is tri- 
angular in shape, with a small lagoon extending along the eastern and 


the northern faces of the island (Plate 9). The lagoon is comparatively 
shallow, not having anywhere a depth greater than five fathoms. Nearly 


i" 


Mee ow Lee 
Ta ye a A : 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 67 


the whole lagoon is covered with patches of corals and of reef rock, espe- 
cially in the southern and western parts. The island of Vatu Leile is 
a mass of elevated limestone rock, rising at the southern extremity to 
bluffs of about 30 feet on the western side. The series of bluffs forming 


WEST SIDE OF VATU LEILE. 


the western shore gradually increase in height as we go north, where at 
the most westerly point the bluffs are more than 100 feet in height 
(Plate 100). 

The bluffs of the western coast are vertical faces with rounded summits 
full of cavities and alternate with short coral sand beaches. On many 
parts of the fringing reef edging the west coast there are still left small 
mushroom-shaped rocks, fragments of elevated limestone rock once form- 


NORTHWEST POINT OF VATU LEILE. 


ing a part of the main island. The northern extremity of the island is 
full of caves. Judging from the color of the water, the outer slope of the 
reef flat towards deep water appears to be very gradual. The whole island 
slopes gently to the eastward, having gradually been denuded and eroded 
so as to form a low east shore line, with extensive flats off the north- 
eastern point. The west shore is protected by a fringing coast reef 


68 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


varying in width from a few yards te 300 or 500 yards, or even disap- 
pearing entirely along some of the beaches, with many areas of smooth 
impounded water within the fringing reef flats. The north side of the 
lagoon is protected by an outer reef flat fully half a mile wide in some 
places. On it corals are flourishing. There are two passages into the 
lagoon, with about ten feet of water in the channel. On the eastern 
side the outer reef runs parallel with the coast, gradually becoming wider 
towards the south, where it forms a wide coral flat connecting as a frin- 
ging reef the outer reef with the low southern part of the island. 

To the west of the lee passage are the small island of Vatu Savu 
(Plate 101), consisting of a larger low rock of elevated limestone deeply 
undercut and pitted and honeycombed, and of three other mushroom- 
shaped rocks of the same structure. Between the lee and the weather 
passage are the islands of Vatu Levu and the cluster of rocks Vatu 
lai lai (Plate 102), similar in structure and in appearance to Vatu Savu. 
These islands and islets are all situated upon the flat of the outer reef. 
The whole reef flat is further studded with negro-heads, the remnants of 
former islands and islets of elevated limestone. 

The presence of these islands, islets, and rocks, as well as the existence 
of the extensive flats off the east coast, clearly indicate the manner in 
which denudation and erosion have transformed the greater Vatu Leile 
which once may have covered the whole area of the lagoon, leaving only 
a part of the main island, with the islands and islets on the outer reef 
flats and the innumerable patches of corals flanking the inner edge of the 
outer reef. There is a strong current flowing out through the passages 
of the northern line of the outer reef. 


THE SOUNDS OF FIJI. 
Plate 22. f 


Fulanga is also interesting as illustrating the formation of an atoll by 
the same causes which have produced the Sounds in the Bermudas.’ 
In the case of Fulanga we have a ring of elevated coralliferous lime- 
stone raised by volcanic agencies to a height of nearly two hundred feet. 
The whole area of Fulanga was probably once covered by coralliferous 
limestone, forming an island resembling Kambara or Mango. The island 
was, judging from its present condition, highest on the northern side, with 


1 Bull. Mus. Comp. Zoél., Vol. XX VI. No. 2, 1895, p. 231; also Bull. Mus. Comp. 
Zobl., Vol. XX VIIL. No. 2, 1896, p. 29. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 69 


summits nearly as high on the southwest coast, and sloping seaward 
towards the east (Plate 80). Atmospheric agencies gradually reduced 
its height, cutting out at the same time an interior basin, the eastern 
rim of which (Plate 81), being lowest, was soon denuded and eroded in 
part. One can readily see (Plate 22) how longer denudation and ero- 
sion would reduce the existing Fulanga land to a few large islands left 
isolated in the interior of an encircling reef and connected only by a few 
mushroom-shaped or conical islets, the interior of the lagoon being 
dotted with coral heads, the recent corals on the outer edge of the sub- 
marine flat forming a reef crust of moderate thickness. This coral rim 
has been broken through, and the action of the sea has gradually 
hollowed out in the interior a circular sound resembling an extinct crater 
(Plate 22), which has arisen solely from the disintegration of the inner 
part of the elevated limestone. Many parts of this still exist as small 
mushroom-shaped or conical islands (Plate 83). 

It is also probable that some of the ancient elevated reef flats may 
have been converted into atolls by causes similar to those which have 
produced the crater-like Sound of Fulanga. This has perhaps been the 
case with such atolls as Ngele Levu, and the Oneata, Ongea, and Yan- 
gasi groups. In both Ongea Levu and Ongea Ndriti (Plate 22), incipient 
sounds are forming which will cut these islands into two or more com- 
ponents, each one of which will in its turn be dissected into smaller 
islands or islets, till finally the remaining land may be all reduced to 
insignificant islands and islets, as on Ngele Levu (Plate 17), or on Wai- 
langilala (Plate 18), Reid Haven, Vanua Masi (Plate 20), Motua Levu 
and Motua lai lai, Duff and Adolphus Reefs (Plate 18), or the islets may 
have totally disappeared and no vestige of the former land area remain 
except the sunken coral heads and rocks of such atolls as Thakau Levu, 
Thakau Motu (Plate 22), Thakau Lekaleka (Plate 21), the Ongea 
Reefs (Plates 20, 21), Thakau Tambu (Plate 20), Thakau Mata Thuthu, 
and Thakau Vutho Vutho (Plate 17), with the reservation that some of 
these atolls may be the result of the denudation and submarine erosion 
of volcanic islets or peaks or ridges, and not necessarily of elevated 
coralliferous limestones. 

Are not islands such as Phoenix, Birnie, Kean, Howland, Baker, and 
Enderbury, which have depressions in the centre and no lagoons, islands 
which are gradually being denuded to the level of the sea, and the next 
stage of which will be the formation of a lagoon (sound) by the cutting 
in of the sea across the rim at one or more points, forming islands or 
islets round the lagoon? We can thus explain the peculiar formation of 


70 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


these islands without having recourse to subsidence. Yet other writers 
upon coral reefs would look upon some of these islands as instances of 
raised atolls. 

The gradual transformation of islands, composed either wholly or in 
part of elevated limestone, into islands with large interior sounds like 
Fulanga can be readily followed by examining such islands as Wangava 
(Plate 22), Tuvutha, Naiau (Plate 20), or Vanua Vatu (Plate 21), in 
which the interior basin is still surrounded by a high rim. Next fol- 
lowed such islands as Mango (Plate 19), in which the interior basin has 
at one extremity been transformed into a diminutive sound ; then follow 
such islands as Namuka (Plate 22), the rim of the basin of which has 
been eroded so as to leave only parts of it, and the outline of which has 
been deeply cut into by a large outer sound. We pass next to such a 
group as Ongea (Plate 22), and next to such groups as Yangasa (Plate 
22), of which the rim of the basin is represented only by four smal] 
islands scattered within the encircling reef; next to Oneata and Aiwa, 
where a single island, comparatively small, represents the former extent 
of the elevated limestone area of those groups. And a still further stage 
of erosion and denudation is represented, as stated above, by Ngele 
Levu, Wailangilala, and other atolls in Lau. 

Vatu Leile (Plate 9) must have sloped very rapidly eastward to have 
attained its present condition, and we can readily follow it to a time 
when it will be flanked on the west side by a line of narrow islets very 
similar to those now existing on the north side of the lagoon. When 
the island and islets in Vatu Leile, Ngele Levu, Wailangilala, Katavanga, 
Reid Reef, Aiwa, Oneata, Yangas4, and Ongea have disappeared by sub- 
sequent erosion, it will be wellnigh impossible to detect the nature of the 
substratum upon which the modern reef is growing. At that time the 
lagoon will probably have become gouged out much as Ngele Levu has 
been. A similar difficulty will naturally be encountered, though at a 
later period, in determining the geological composition of the substratum 
underlying the modern coral reef in the atolls of Wakaya, Makongai 
(Plate 15), Mbengha (Plate 8), North and Great Astrolabe Reefs (Plates 
9, 10, 11), Budd Reef (Plate 18), Totoya (Plate 16), Kimbombo 
(Plate 19), Nairai (Plates 12,14), Komo (Plate 22), and others, when 
the islands now existing on the edge or within the encircling reefs have 
disappeared from denudation and submarine erosion. 

This is another instance of the great variety of causes which have been 
active in producing the present physiognomy of the reefs of the Fijis, 
and shows the impossibility of assigning any one factor, like subsidence, 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. aL 


for instance, as is done by Dana and Darwin, as the single cause for 
the formation of the many different kinds of atolls and of barrier reef 
islands to be found in the Fijis. 


THE TERTIARY ELEVATED LIMESTONES OF FIJI. 


The existence throughout Fiji of numerous platforms of submarine 
erosion at average depths varying within very moderate limits seems to 
indicate a condition of approximate equilibrium as far as either elevation 
or subsidence is concerned. The elevation of the limestones of late 
tertiary age clearly indicates that the origin of the greater number of 
the Fiji Islands dates back approximately to that period. This is un- 
doubtedly the case with the range of islands known as the Lau or Eastern 
Archipelago of Fiji. With them we should include the more northerly 
islands, the group to the east of Ngamia, and of Budd Reef, including 
Thikombia. 

It is more difficult to determine the age of the larger islands, Viti Levu 
and Vanua Levu, as well as Taviuni, Kandavu, and the voleanic islands 
of the Koro Sea. We may assume with a certain degree of probability 
that the age of such islands as Nairai and Ngau corresponds with the 
age of the volcanic rocks which have lifted the islands of the Lau group 
to their present altitude. But in Viti Levu and Vanua Levu the 
problem is more complicated. While elevated coralliferous limestones 
of late tertiary age occur along the shores of Viti Levu evidently of the 
same age as the limestones of Lau,’ yet there is evidence of the existence 
of older rocks as a nucleus of the larger Fiji Islands. So that until the 
geology of Viti Levu and of Vanua Levu has been more accurately 
studied, we must leave their age undetermined ; but enough is known 
of the geology of the shore line to show that the existence of the great 
barrier and fringing reefs along the shores of Viti Levu and of Vanua 
Levu gives no evidence that the great barrier reefs of these islands owe 
their origin to the gradual subsidence, during our epoch, of the islands 
themselves. 

The existence of the tertiary elevated coralliferous limestone at so 
many points in the Fiji Archipelago (Plate 2) seems to indicate a huge 
limestone bed of great thickness and extent, formed during tertiary times, 
along the flanks of ancient volcanic islands, and elevated by subsequent 
intermittent volcanic action during more recent times over areas of 


1 Horne (A Year in Fiji, London, 1881, p. 165) says that in Viti Levu and Vanua 
Levu sedimentary or limestone rocks are found on all mountains. 


fe BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


varying dimensions, — areas which might be of considerable extent, like 
the Exploring Isles, the Argo Reefs, or smaller areas, like Yangasé, 
Oneata, Ongea, Fulanga, and the like, or smaller peaks forming atolls of 
very limited circumference, like Wailangilala, Nuku Mbasanga, or iso- 
lated limestone rocks of still smaller dimensions, like Vekai, Tavunasithi, 
and others. 

Of course numerous soundings among the islands of the Eastern Archi- 
pelago of Fiji are needed to ascertain the existence of a more or less 
continuous plateau of coralliferous tertiary limestone deposited either by 
accretions upon its surface or formed during subsidence. 

I brought to Suva a complete diamond-drill boring apparatus and a 
competent man to superintend the work, Mr. William Eyers, recom- 
mended to us by the Sullivan Machine Company of Chicago, from whom 
the apparatus was obtained. A comparatively small hand machine was 
sent, capable of drilling to a depth of from four to five hundred feet ; 
an oil motor was also provided to expedite the work with increasing 
depth. This machinery had been shipped when information reached 
the United States that Professor David of the University of Sydney 
had left for Funafuti in charge of an expedition to take up the work 
where it was left by Professor Sollas, the head of the expedition, assisted 
by the council of the Royal Society of London.* The day before leaving 
Cambridge for the Pacific, we heard that Professor David’s party had 
succeeded in reaching a depth of nearly 600 feet, the bottom being still 
in coral. This information seemed to settle the coral question, and all 
I hoped to accomplish was merely to confirm the work of Professor 
David by boring in some other district. Subsequent information re- 
ceived from him leads me to think that the matter is not so simple 
as represented by the newspapers, and from what I have seen thus far 
in the Fiji Island reefs I can only conclude that the boring at Funafuti 
has settled nothing, and that we are still as far as ever from having a 
general theory of the formation of coral reefs. In fact, with the present 
information obtained in Fiji, I should never have thought of boring in 
the atolls of that group, for reasons which will be given presently. 

This evidence shows that any result obtained would merely indicate 
the thickness of the former elevated limestones at any particular point ; 
information which could have no bearing on the main question, if I am 


1 T have to thank the Trustees of the Bache Fund of the National Academy of 
Science at Washington for an appropriation of $1,200 towards defraying a part of 
the expenses of the boring. 

2 Proceedings of the Royal Society of London, March, 1897, p. 502. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 73 
correct in my interpretation of what I have observed ; information, in 
fact, which may be obtained as one steams along, without the trouble or 
cost of boring. Should I be correct in my inference, I am inclined to 
look upon the boring at Funafuti much in the same light, and to assume 
that that island is also in an area of elevation, as well as others in the 
Ellice group, and that the great thickness of coral obtained was reached 
in the base of an ancient limestone, and that the results obtained by the 
boring there do not assist us in any way in corroborating the theory of 
subsidence as essential to the formation of atolls. 

The evidence which has been brought forward regarding the great 
thickness of modern reefs, as postulated by Darwin, from that of the fos- 
sil coral reefs existing during former geological periods, seems to me to 
be of little valne. Langenbeck? and von Lendenfeld? have both urged 
this point. The former has given an excellent résumé of the subject of 
these ancient reefs, although he has no personal knowledge of recent 
reefs. All that can be said at present is that these so called fossil 
reefs are coralliferous limestones of great thickness, which first occur in 
the Devonian ; they are little developed eitber in the Permian, or Trias, 
or Lias. They are again well developed in the Jurassic period, less so 
in the Cretaceous, and increase in Tertiary times. That parts of some 
of these coralliferous limestone masses represent reefs there can be little 
doubt, yet the observations we made in Fiji regarding the coralliferous 
elevated Tertiary limestones, which have been considered as elevated 
reefs of the present epoch, only show how guarded we should be in an 
expression of opinion as to what constitutes a fossil reef, —I mean a 
fossil fringing or barrier reef, or a fossil atoll, —when we are not able to 
decide that point in the reefs of to-day, and when one set of observers 
claims that the Tertiary elevated limestones represent elevated atolls, 
while the other set clearly shows that these elevated limestones have 
played no part in the formation of the recent atoll, or barrier reef, but 
have merely built up the substratum upon which the moderately thin 
crust of recent reefs has established itself. 

Granting, even, as is very probable, that when these Tertiary lime- 
stones were formed they were formed in great part by subsidence, 
and in part by accretion from the carcasses of the invertebrates living 
upon their surface, this would in no way help us to a satisfactory 


1 Langenbeck, R.: Die Theorien iiber die Entstehung der Koralleninseln und 
Korallenriffe und ihre Bedeutung fiir Physische Fragen. Leipzig, Abschnitt IV. 

2 Nature, May, 1890, p. 29. See also the interesting note by von Fritsch, 
quoted by Kramer, loc. cit., p. 38. 


74 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


explanation of the formation of atolls and of barrier reefs by the growth 
of the corals of the present epoch. Nor would the geological evidence of 
the great thickness of similar limestones in past periods be of any 
assistance in the solution of the problem if our explanation of the 
formation of atolls and of barrier reefs upon platforms of submarine 
erosion is correct. 

Certainly the analogy of the association of volcanic rocks and so 
called reefs in the Devonian and Trias with similar association in the 
Pacific has no value, as is suggested by Frech? and Langenbeck. The 
substratum upon which corals may grow depends upon the geological 
structure of the country and its latitude. Such an analogy would 
throw out in great part the reefs of Australia, those of Florida, of the 
Bahamas, of Honduras, and of the northern coast of Brazil, which are 
not in volcanic regions, and where the substratum is either Cretaceous 
or Tertiary. 

The only evidence we have of the great thickness of coral reefs, such 
as is required by the Darwinian theory of the formation of atolls and 
of barrier reefs, is based upon the great thickness of the so called 
elevated reefs observed in the Pacific by Dana, Darwin, and others, and 
upon similar observations in Cuba and other parts of the West Indies, 
and upon the evidence of the great thickness of the reefs of the Dol- 
omite. That the latter are true coral reefs is more than doubtful. 
Those rocks are probably great masses of limestone similar to the huge 
deposits of so called elevated reefs of the West Indies and of the Pacific. 
The evidence obtained by boring, and from recent elevated reefs, shows 
that the modern coral reef attains but a moderate thickness well within 
that of the depth at which reef corals grow. The limestones form 
the basis or substratum upon which the recent reefs have obtained 
a footing. The elevated reefs of Cuba and of the West Indies have 
been shown to be Tertiary coralliferous limestones, and the same is the 
case with the elevated reefs of the Pacific, if we can judge of their 
age by that of the elevated coralliferous limestone reefs resembling 
them observed by me in Fiji. 

The central depression, noted as characteristic of the summit of so 
many islands consisting of elevated coralliferous limestones does not show 
these islands to be elevated atolls as has been supposed. The summit 
basin representing the former lagoon of the island has been formed since 
the elevation of the island by atmospheric agencies. This basin is a 
gigantic banana-hole, as such depressions are called in the Dahamas, 


1 Neues Jahrb, f. Mineral., 1892, Pt. II. p. 173. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 75 


formed by the carrying off the limestone in solution in the pools or ponds 
in the summit basins, — basins which with age become deeper and deeper, 
forming thus depressions which in some instances have been mistaken, 
in the one case for extinct craters, in the other for the lagoons of 
elevated atolls. 

I would refer to the description of such islands in Fiji as Mango, 
Kambara, Tuvutha, Naiau, Fulanga, and others, as evidence supporting 
the explanation here given of the formation of the so called elevated 
atolls. Of course I do not mean to assert that an atoll cannot be 
elevated as such, nor that such atolls may not exist. I merely wish 
to assert that the summit basins of islands formed of elevated cor- 
alliferous Tertiary limestones in Fiji are islands in the first stage of 
disintegration, passing gradually from such types as Naiau? and the 
like to islands like Mango, then to Fulanga, next to the Yangasa cluster, 
then to Ngele Levu, and finally to Motua lai lai and the like. 

The steepness of the slopes of coral reefs has been assumed to be due 
to the growth of corals, and has generally been taken from old and unre- 
liable soundings, as has been stated by Admiral Wharton? and others. 
The great depths are generally soundings so far off from the coral islands 
as not to give any accurate information. 

The actual slopes of coral reefs which have been measured are very 
few, and the slopes given are invariably those of the underlying sub- 
stratum, which may or may not be steep, and the inclination of which 
has no bearing on the angle of the steep outer slope of recent coral 
reefs, which usually reaches only to the very moderate depth of twelve 
to fifteen fathoms, 

It seems to me that the calculations which have been made by Dar- 
win in regard to the thickness of coral reefs, depending as they do upon 
the assumption that their great thickness has been formed by sub- 
sidence, and that this thick mass rests upon the continuation of the 
inner land slope under the coral reef, are assumptions which cannot be 
proved, or have not been proved. We should get a totally different 
result, that of a comparatively thin crust, if we assume that the land 
slope commences at or near the outer edge of the reef wherever the out- 
ermost negro-heads have been found. And in a great many cases, the 
steepness of the sea face is no greater than the slope of the mountains 
of the adjoining land. I have already called attention to the fact that 


1 Naiau itself having become depressed in the centre by chemical and atmos- 
pherie erosion. 
2 Nature, June 19, 1890, p. 172. 


76 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


off the south coast of Cuba we have along the sides of Bartlett Deep 
fully as steep a pitch as that of any coral reef. 

Gardiner’ has noticed the atoll-shaped shoals inside the great barrier 
reef of Fiji (Plate 23*), and compares them to the smaller atolls inside 
the large atolls of the Maldive group. See also the Serpuline atolls of 
. the Bermudas,’ which hold the same relation to the lagoon inside the 
outer barrier as the atoll-shaped shoals just mentioned hold in Fiji, 
and they certainly are not due to the effects of the débris of the outer 
reefs of the present day, as is claimed by Dana. 

As long as it was taken for granted that the coral reefs of the present 
day were of great thickness, it was natural to compare them with the 
great beds of coralliferons limestones occurring in past ages from the 
time of the Devonian to the end of the Tertiary period. While there is 
abundant proof that some of these limestone beds have been formed 
during a period of subsidence, there is also ample proof that they must 
have greatly increased in thickness by accretion. But it does not follow 
from this that atolls and the lagoons of barrier reefs have been formed 
during a period of subsidence, now that we know that a great many of 
the coral reefs of the present day attain a comparatively moderate thick- 
ness, well within the bathymetrical limits at which reef building corals 
thrive. Nor is there anything to prove that these ancient limestones 
represent such modern structures as the atolls, or bordered the lagoons 
of barrier reefs, and even if they did it is more natural to suppose that 
the lagoons of these ancient atolls, as well as those within the ancient 
barrier reefs, must have been formed by the same agencies which have 
shaped the atolls and the lagoons of barrier reefs in our days. So that 
the analogy between ancient and modern reefs, such as is upheld by Dr. 
R. von Lendenfeld,®? while undoubtedly true as far as it applies to the 
formation of beds of coralliferous limestones of great thickness, yet has 
no application to the actual formation of the lagoon of an atoll or of a 
barrier reef. 

This still leaves open the question of the mode of formation of such 
thick masses of coralline and coralliferous limestone, which, though they 
may originally have been formed partly by subsidence, may also have 
been formed partly by the gradual pushing out to seaward of the outer 
edge of a reef increasing both in height (depth) and in width by the con- 
stant pushing out of the mass of débris and of blocks detached from the 
Loe. cit., p. 498. 


Bull. Mus. Comp. Zool., Vol. XX VI. No. 2, 1895, p. 253. 
Nature, No. 1071, May 8, 1890, p. 29. 


as woe = 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. a 


outer edge upon which corals may flourish and spread seaward, when 
the talus has reached the depth at which corals can grow. I am in- 
clined to think that the examination of such a reef will alone give us 
an idea of the way in which such thick masses of coralliferous lime- 
stones were formed, —— most probably by a combination of subsidence, 
of accretion, and of lateral expansion. 

What the exact age of the elevated limestones is, I am as yet unable 
to state. Their aspect and position show them to be of considerable 
age, and probably antecedent to the present period, and in many ways 
they resemble some of the late tertiary elevated limestones I have found 
on the north coast of Cuba. The great thickness which the elevated 
coralliferous limestones attain in this group, at least 800 feet, also 
shows that it may have been deposited during a period of subsidence, 
but not a period of subsidence in our epoch, or which could have had 
any effect in shaping the outline of the islands of the Fiji and their 
accompanying reefs, 

Whether the elevation of the Fiji group corresponds in time with that 
of the northern part of Queensland, Iam unable to state. I can only 
suggest that it is not improbable that the elevation of Queensland and 
of the islands to the east of the Solomon, New Hebrides, etc., including 
the Fijis and Samoa, may have been synchronous, and that these islands 
have, like northern Queensland, been subject to an immense denudation 
and erosion, reducing them to their present proportions. The elevation 
haying probably, as in northern Australia, been preceded in still earlier 
geological times by a great depression, during which the thick beds of 
coralliferous limestone may have been formed. Judging from some pho- 
tographs I have seen, I should feel inclined to consider the atolls of the 
Paumotus to have been formed by causes similar to those which have 
shaped those of the Fijis. 

The Tonga Islands as described by Lister! are arranged by him in 
three divisions: (a) purely volcanic islands; (0) islands formed of 
volcanic materials laid out beneath the sea and since elevated, with or 
without a covering of reef limestones; and (ce) islands formed entirely of 
reef limestones. 

The islands of the Vavan group consist entirely of limestone, the for- 
mation of which must have been at least 300 feet thick. The islands are 
flat-topped, and the majority stand at one of three levels of elevation. 
Lister? figures the terraces of the islands to the south of Vavau. At 

1 Notes on the Geology of the Tonga Islands. By J. J. Lister. Q. J. Geol. 


Soe. of London, Vol. XLVII. p. 590, 1891. 
2 Loc cit., p. 608. 


78 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY, 


Fiji the only signs we saw of terraces were at Yangasé. The terraces 
in Fiji are most obscure, and what we find of elevation would seem to 
indicate sudden and rapid elevation without periods of rest such as 
occur in the Vavau Islands of the Tonga group, or in Cuba, where the 
terraces are so well marked, especially in the vicinity of Cape Maysi.? 

Lister speaks of the peculiar shape of the groups, penetrated by long, 
narrow, and deep inlets of the sea, a condition of things very similar to 
that of Ngillangillah, and of the north shore of Vanua Mbalavu in 
Fiji. Tongatabu is formed of coral limestone throughout, and one often 
meets with patches of coral, many feet in diameter, on which the lines 
of Astrzoids or Madrepores are seen radiating from a common centre. 

Lister calls attention to the basis for the growth of coral reefs which 
can be formed by such islands as Falcon Island.? He also shows that 
in the Tonga Islands, Tongatabu and Nanuku rest on shallow banks, 
and where the basis is exposed it is shown at Nanuku and Eua to consist 
of layers of volcanic material laid out under water. 

Darwin and Dana both suggested that the formation of the Tonga 
Atolls was in a period of subsidence, yet it is asserted in the discussion 
of the subject* by Mr. J. W. Gregory that his theory (Darwin’s) was 
not proposed for areas of coral formation in shallow or rising areas. 
Why then do Darwin and Dana quote them as examples of their theory? 
There is altogether too much of that kind of argument in the discussion 
of that theory. Are Darwin’s supporters at liberty to carry on the 
process of selection till nothing is left of the original statement ? 

In Samoa and Tonga the volcanoes are still active, and we can, follow- 
ing Lister, actually trace the process of elevation and of erosion which 
has resulted in Tonga in elevating limestones and volcanic islands similar 
in every respect to those we have observed in Fiji. Islands in the last 
named group owe their existence to former volcanic action, the evidence 
of which is still visible in the existence of the extinct craters of Taviuni, 
of Thombia, of Moala, and of Totoya, and this volcanic action is to be 
traced throughout the larger islands of the group. 

The description of Eua Island in the Tonga group given by Com- 
mander Oldham in Nature of May 22, 1890, p. 95, applies admirably to 

1 A. Agassiz, A Reconnoissance of the Bahamas and the Elevated Reefs of Cuba. 
Bull. Mus. Comp. Zodl., Vol. XX VI. No. 1, p. 110, 1894. 

2 R. T. Hill, Notes on the Geology of the Island of Cuba. Bull. Mus. Comp. 
Zool., Vol. XVI. No. 15, 1895. 

8 Falcon Island is stated to have disappeared during an eruption in August, 


1898. 
4 Q. J. Geol. Soc. of London, Vol. XLVIT. p. 590, 1891 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 79 


the conditions which I imagine to have existed in the Fijis,’ although the 
terraces indicate two periods of elevation, with one of rest, during which 
an interior basin similar to the central basin of islands like Kambara, 
Wangava, and the like, in Fiji, was formed by atmospheric agencies 
probably. 

The rocks underlying the coralliferous limestones are stated by Pro- 
fessor Judd to be igneous rocks, but not modern volcanic material. 
He says, “They are suggestive of ancient volcanic masses that have 
been exposed at the surface by denudation, . . . and it is quite incor- 
rect to quote examples like this as lending support to the view that all 
oceanic islands are of volcanic origin.” 

Speaking of Eua, which belongs to group (b), Murray according to 
Lister is of the opinion that the organic deposits of the island are old, 
yet there is no satisfactory evidence to refer them to the Tertiary 
period. 

Niue cr Savage Island is an elevated coralliferous limestone island, 
said to be 200 feet high ;? the younger Foster considers that the cen- 
tral plain represents an ancient lagoon. It is skirted with enormous 
caverns. 

The figure and description given by Dana® of Metia or Aurora Island, 
one of the Western Paumotus, recalls many of the raised limestone 
islands of Fiji. In the Hervey group at Atiu similar caverns exist, and 
they have also been noticed by Captain Beechey at Henderson Island. 
Its cliffs worn into caverns rise abruptly to about 230 feet on all sides 
except the south, where the island slopes very abruptly, much as Vatu 
Leile in Fiji. The surface of Metia, as described by Dana, resembles 
closely that of Ngele Levu, and he describes the wide shore platform, 
“resembling that of the low coral islands”? and the modern reef about 
its margin. 

It will be interesting to see if the great masses of coral blocks, figured 
and mentioned by Dana‘ may not throw some new light on the nature 
of the substratum of some of the Paumotus, where he observed them. 

The sections of the small island of Mas4émashu in the Red Sea® do 
not seem to me to indicate subsidence, as is stated by Bonney (p. 312). 


1 See also the account of Eua, by J. J. Lister, in Q. J. Geol. Soc. of London, 
Vol. XLVII. p. 590, 1891. 

2 Sailing Directions, Pacific Islands, Vol. II. p- d4. 

8 Loc. cit., p. 193. 

$ Loe. cit., pp. 179 and 203. 

5 Nature, Vol. XXXVI. p. 413. 


80 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


‘ 
On the contrary, judging from Fiji analogy, the section indicates the 
elevation of a submarine bank of coralliferous limestone and its subse- 
quent denudation, and the forming of an enveloping reef on its summit 
having no relation with the nature of the deeper sea slope. 

We collected a number of corals from the elevated limestone rock at 
several localities along the south and west coast of Viti Levu, at Suva, 
Ngele Levu, Kambara, Ongea, Ngillangillah, and Oneata. I found it 
impossible to determine whether the corals were 7m situ, or had been 
rolled or dropped along the sea face to form a talus. The difficulty of 
determining this without very considerable blasting at the base, the 
face, and along the exposed slopes of the elevated coralliferous lime- 
stones, is very great. 

The collecting of corals from the exposed faces of the cliff was almost 
hopeless with our appliances. The faces have become extremely hard, 
a hammer produces no impression, and the corals are so well embedded 
as to make it impossible to cut them ont. 

It seems impracticable, except where one can actually see the corals 
grow along a slope, or on a patch or the sides of a head, to determine in 
the elevated reef rock if they are still in their natural attitudes. Madre- 
pores and Pocillopores grow in all kinds of position ; so do the heads of 
Astreeans, Mzandrinas, and other massive corals. Furthermore, the 
spaces between coral patches and heads and individual masses of coral 
reef are filled either with sand, corallines, or fragments of dead corals. 
. We can easily see the difficulty of recognizing the former condition of 
corals now embedded in a homogeneous mass of hard ringing limestone, 
in which the corals often exist as more or less indistinct solidified masses, 
barely indicating the genus to which they belong. The coral and coral- 
line sand have become solidified into a close limestone ringing to the 
hammer. Large spaces have become impregnated with the red earth, 
characteristic of coral limestone formations, and the masses of coral 
fragments form a breccia or puddingstone of corals of the species which 
once flourished on the reef. Masses of Nullipores and Orbitolites are 
similarly cemented, or form the connection between the individual 
masses. The whole again is more or less cavernous, representing either 
spaces originally existing on the reef, or cavities which have been formed 
by the percolation of water through the mass. As far as I have exam- 
ined the corals collected from the elevated limestones, they appear to 
belong to the same genera as those now living. 

A careful and extended examination of one of the elevated coralliferous 
limestone reefs, as at Vanua Mbalavu or Kambara or Mango, for instance, 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 81 


where we can begin the study at the very base of the elevated limestone 
reef at its point of contact with the underlying volcanic rock, will teach 
us a great deal regarding the interior structure of a coral reef. This we 
can follow to the surface, or nearly so, by following the faces of exposed 
cliffs or the slopes of the ridges. Ofcourse, the uppermost part of the reef 
rock, that which formed the original surface of the reef, will have been 
denuded and eroded to a considerable depth. But it ought to be possible 
from the study of an extensive area of an elevated reef, both vertical 
and horizontal, to settle the question of the growth of a reef seaward by 
its gradual extension upon a talus formed at a comparatively shallow 
depth (say twenty fathoms) from the fragments and masses which have 
dropped at the foot of the sea slope of the reef, after having been de- 
tached by the action of the breakers from the edge of the reef. It is 
natural to suppose that there must exist at the base of the reef a num- 
ber of coral masses, judging from the multitude which are thrown upon 
the sea face of any modern reef when exposed to violent breakers. 

Dr. William H. Dall? has been kind enough to examine the fossil 
mollusks which I collected from the elevated limestone reefs in the 
Fijis. He confirms the impression I had formed of their late tertiary 
age. Dr. Dall writes: “The fossils comprise Turbo, Cassis, Lithophaga, 
Macha, Tellina, Meretrix, Dosinia, Chama, Pholas, and fragments of 
Pecten. None of the genera are extinct. The rock, however, looks 
decidedly too old for Pleistocene. I should say the fossils were younger 
than Eocene, and might be either Miocene or Pliocene.” 

The boring which I started at Wailangilala Island in the atoll of the 
same name reached at forty feet a limestone similar in all respects to 
that composing the elevated reefs we had observed at Ngele Levu, 
at Vanua Mbalavu, at’ Mango, at Yangasd, at Oneata, at Ongea, at 
Kambara, at Vatu Leile, and at different points along the eastern, 
southern, and western shores of Viti Levu. At some points the elevated ” 
limestones attain a height of over 1,000 feet (Vatu Vara Island 1,030 
feet), and the volcanic rocks underlying the elevated limestone reefs 
were observed at Vanua Mbalavu, at Mango, at Kambara, and at several 
points along the southern and western coast of Viti Levu. A renewed 
examination of the elevated reefs of the Paumotus, of the Friendly 
Islands, of the Gilbert, Ellice, and other groups of atolls in the Pacific 
will be needed to determine their age and correlation to the Fiji ele- 
vated limestones. At any rate, it is evident that the tertiary corallif- 
erous limestones of Fiji have not played any part in the formation of 


1 See Am. Journ. Science, Vol. VI. p. 165, 1898. 
VOL. XXXIII. 6 


82 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


the atolls or islands encircled by recent coral reefs beyond forming the 
substratum upon which the recent corals have grown and established 
themselves as a comparatively thin crust. 

The underlying limestones have performed exactly the same part as 
the volcanic substratum in other islands of Fiji, such as Totoya, Kim- 
bombo, Wakaya, Makongai, Moala, Nairai, Ngau, and others. In both 
cases the platform upon the edge of which the corals grow has been 
prepared by extensive submarine erosion, dating from the time when the 
limestones were elevated by the volcanic rocks which crop out everywhere 
in Fiji, —an elevation which was not necessarily synchronous throughout 
Fiji and may have taken place at several distinct periods, so as to make 
it often difficult to determine the relative age of the limestones and of 
the volcanic masses. 

Professor David, of the University of Sydney, has been kind enough to 
assist me in obtaining the services of one of his students, Mr. E. C. 
Andrews, to collect fossils from the elevated limestones of Fiji. Mr. 
Andrews has spent a part of the summer in Fiji, collecting material and 


exploring in detail some of the faces and slopes of the elevated reefs of 
the Archipelago, and has obtained ample material to determine the age 
of these elevated limestones. 

In the earlier discussions of the thickness of recent coral reefs by 
Darwin and Dana, no attention was paid to the possibility of the sub- 
stratum of recent reefs consisting of tertiary limestones. Elevated lime- 
stones containing corals of tertiary age were considered as of recent 
origin and as pointing to a great thickness of modern reefs. It has 
been shown in Florida that the modern reef is not more than about 
50 feet thick, and is, according to the borings from the artesian well at 
Key West, succeeded by tertiary limestones, in which corals oceur at 
intervals to a depth of 2,000 feet. 

It has been stated by Dana and others that the borings from the 
artesian wells at Honolulu, to the rear of the shore line of the fringing 
reef of Oahu, indicate a great thickness of modern reef corals. These 
statements are based upon the examination of samples of finely ground 
particles of limestone accompanied by an occasional fragment of coral, 
the age of which has not been determined. The statements are further 
supported by the evidence of Mr. J. A. McCandless, the engineer in 
charge of the boring, who asserted to both Mr. Dana and myself that in 
boring all his wells the tool passed through a great thickness of corals, at 
various levels. During my recent visit at Honolulu, I was so fortunate as 
to be on the spot where Mr. McCandless was boring a ten-inch well, about 


ETS I == 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 83 


2,500 feet from the shore line, and perhaps seven feet above high water 
mark. Down to a depth of 80 feet nothing but recent reef coral rock 
was encountered, but from that point to a depth of over 300 feet the 
limestone passed through was of a very different character. It contained 
but few corals, being composed almost entirely of the shells of mollusks, 
mainly bivalves. The rock was white, chalky, and resembled in every 
way the rocks of the Vicksburg age of Florida and of Yucatan ; but its 
age has not yet been accurately determined. Enough, however, is clear 
to show that the limestones which form the substratum upon which 
rests the recent fringing reef of Honolulu do not belong to the present 
period. Mr. McCandless assured me that limestones like those I had 
the opportunity of examining while the boring was going on are identi- 
cal with those to which he called Mr. Dana’s and my attention in 1888, 
and that until I pointed out to him that the white limestone was almost 
wholly made up of mollusks he had only paid attention to the occurrence 
of occasional corals, and supposed that the lower limestone formed the 
continuation of the recent modern reef. But, as I have stated, this 
lower limestone differs from reef rock both lithologically and in its being 
mainly made up of fossil mollusks. 

It is very clear that when boring in a coral reef district in which it 
is difficult or impossible from other data to determine what geological 
changes may have taken place, or the probable age of any limestone we 
may pass through in boring, it may be very easy to draw wrong conclu- 
sions both as to the age of the limestones and regarding the position of 
the line of demarcation between the modern coral reef and the under- 
lying older limestone substratum. 

If my conclusion is correct, that such atolls in the Fiji Islands as Wai- 
langilala, Ngele Levu, and many others to which I have referred in this 
report, are formed upon platforms of submarine erosion of elevated ter- 
tiary limestones, and if, further, in similar atolls in the Paumotus, the 
Gilbert, Ellice, and other groups, the substratum underlying the mod- 
ern coral reef is likewise composed of tertiary limestones, it will become 
apparent that such borings as those carried on at Funafuti will not help 
us in any way to solve the problem of the formation of atolls by modern 
coral reefs. Such a boring, even should it reach the underlying volcanic 
substratum, will only give us the thickness of the tertiary coralliferous 
limestone beds forming the substratum upon which the modern coral reef 
has grown, —a thickness which in the Ellice group can only be ascer- 
tained by boring, while in Fiji it can be ascertained approximately from 
the height of the islands composed of elevated tertiary limestones. 


84 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


I take it that the “cliffs” mentioned by Sollas,? and that the pinna- 
cles described by Gardiner? which he calls “the remains of a part of an 
old raised reef,” found on the inner rough zone of the outer reef, are just 
such masses of tertiary limestone as we found throughout the Fijis. 

The shoals described by Gardiner? seem to me to be remnants of this 
elevated reef which have been isolated by submarine erosion, much as 
iu Fulanga and Ngele Levu, and other groups of elevated tertiary lime- 
stone reefs in Fiji, upon which corals grow with greater or less luxuri- 
ance, the bottom of the lagoon between the patches and knolls being 
covered with sand. 

Gardiner* supposed the atoll of Funafuti to have been formed before 
it was elevated. If I am correct in my interpretation of similar reefs 
in Fiji, I think, on the contrary, that the low limestone outer platform 
which now forms the ring of the atoll was once much higher, covered 
a greater area, and has been gradually denuded and eroded to its present 
stage, a process which according to Gardiner and my own observations is 
still going on. 

Hedley,® as well as Sollas and Gardiner, assumes an elevation of four 
feet from the presence of dead subfossil corals in the position of life 
near high water mark. I do not see why the fact that the older lime- 
stones of Funafuti form a cone, and have no connection with the recent 
reef formed upon them, should ‘have any bearing either in favor of or 
against any theory of coral reefs, even if the formation of the corallif- 
erous limestones of Funafuti could only be explained on the subsidence 
theory. The lateral growth of the recent reef inwards and outwards is 
a feature depending, so far as the outer growth is concerned, wholly 
upon the exterior slope of the atoll, and the lateral expansion towards 
the interior of the lagoon depends upon a great variety of causes, such 
as the depth of the lagoon, the character of the islands on the outer edge 
of the atoll, the nature and depth of the shallower windward passages 
leading into the lagoon, the position of the outer reefs with reference to 
the prevailing winds and currents, the geological structure of the sub- 
stratum upon which the recent reef is growing, and many other causes. 
As far as the filling of the lagoon of Funafuti is concerned, the views of 
Gardiner and Hedley are diametrically opposed. The islands may in- 


1 Proc. Royal Society of London, March, 1897, p. 502. Nature, September 24, 
1896, p. 517. 

2 Proc. Camb. Phil. Soc., Vol. IX, Pt. VITI., 1898, pp. 480, 431. 

8 Loc. cit., p 454. 4 Loe. cit., p. 488. 

6 Memoir III., Australian Museum, Part I. Sydney, 1896. 


+ 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 85 


crease in width, and encroach upon the lagoon, but that is a different 
proposition, as shown by Gardiner, from the filling up of the lagoon. 

Gardiner! assumes that the limestones of the Fijis cannot have had 
any different origin from that of many of the atolls and barrier and 
fringing reefs of the present day.” But it seems to me that, inasmuch 
as these elevated limestones are of tertiary age and have been uplifted 
to heights varying from a few feet above the level of the sea to nearly a 
thousand feet to form subsequently platforms of submarine erosion upon 
which the recent reefs have grown, we cannot claim that they have been 
deposited, as recent corals have been, within comparatively narrow batliy- 
metrical limits, the dolomitization of the elevated tertiary limestone 
having gone on to a considerable extent, while that of the recent reefs 
is insignificant. 

Gardiner® looks upon Naiau, Tuvutha, and other islands as perfect 
specimens of raised atolls. I have elsewhere given my reasons for not 
accepting such a view, and for considering the interior depressions of 
such “elevated atolls” as huge sinks similar to those formed in the 
A£olian hills of the Bahamas and Bermudas, and which eventually result 
in the formation of sounds or lagoon-like depressions. Gardiner* does 
not think it possible that denudation owing to climatic causes could 
have been of sufficient importance to have greatly affected the position 
of the summits. It seems to me that the gradation we can trace in the 
summits and outlines of such old island masses as Naiau, Kambara, 
Mango, Fulanga, Ongea, Aiwa, and others indicate, on the contrary, 
a most extraordinary denudation and accompanying submarine erosion. 
Gardiner ® himself has given very much the same examples which I used 
in tracing the gradual changes hinted at above, only he attributes them 
wholly to the solvent action of the sea, while I am inclined to call into 
action in addition the effect of denudation and erosion, and to attribute 
to them a more important share than to the solvent action of the sea 
in the successive stages of the changes in the elevated limestone land 
masses, from an island with a fringing reef to a true atoll. 

Under what conditions these tertiary coralliferous limestones of great 
thickness have been deposited is a distinct question from that of the 
formation. of atolls through subsidence by the upward growth of corals 
during the present geological period. Neither the borings through a 
coral reef growing upon a substratum of tertiary limestone, nor the 


1 Loe. cit., p. 467. 4 Loe. cit., p. 470. 


2 Loe. cit., p. 467. 5 Loc. cit., p. 471. 
4 Loe. cit., p. 470. 


86 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


examination of the outer edge of a coral reef formed upon a substratum of 
volcanic rocks, has given us in Fiji any evidence of the great thickness 
of a modern coral reef. On the contrary, all the evidence I have gath- 
ered there tends to prove that a coral reef forms only a comparatively 
thin crust upon the platform of submarine erosion, whatever be its geo- 
logical structure, upon which it may have found a footing, — a crust of 
modern corals of no greater thickness than that within the bathymetrical 
range of which reef building corals can flourish. 

The examination of the conditions under which beds of coralliferous 
limestone of great thickness have been laid down has little in com- 
mon with the study of the conditions under which a modern reef is formed. 
The study of the conditions under which a modern reef—a reef of the 
present period — is formed and increases in thickness has yet to be made, 
and such a reef must be carefully selected. Probably a broad fringing 
reef resting upon a substratum readily distinguished from the reef rock, 
and one on which there existed a sand key close to the outer edge for 
boring until the substratum was encountered, would be the most suitable. 
But as it would be most difficult to judge from the core obtained at that 
or any other point where the growing reef ceased and the talus began to 
add to the thickness of the reef, it would be necessary to supplement 
this work with soundings taken close together, as well as with an examina- 
tion of the bottom by dredging, either with large or small dredges or 
with trawls and tangles ‘to obtain material in as many different ways as 
possible. Of course we can hardly expect to bring up in this way many 
specimens of reef building corals, hut we can surely, by combining the 
information obtained from the nature of the soundings, the character 
of the bottom as shown in the larger samples secured by the dredge, 
and the occasional fragments of living corals we are sure to bring 
up, form some idea of the exact bathymetrical range to which reef 
building corals extend, and this is not so difficult a problem as is sup- 
posed by Professor Sollas. We should in determining this remember 
that in the interior of large lagoons in which there is an abundant cireu- 
lation of pure sea water close to the inner edge of the outer reef flats we 
have very positive information as to the lower limit to which corals grow 
in abundance. We know that under these conditions the most flourish- 
ing belt of reef builders grows in depths of from three to eight fathoms, and 
beyond that the coral patches decrease very rapidly in number and size, 
that the patches are with increasing depth separated by wider lanes or 
greater areas of coral and coralline sand, or by masses of fragments of 
corals and of dead corals. Wealso know that on the sea face of the outer 


Tp ape” 


eo 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 87 


reef flats wherever they have been examined by means of the sounding 
lead, the dredge, the tangles, and the water glass, identical results have 
been obtained as regards the bathymetrical range of the reef growing 
corals, with the exception that the lower limit of depth seems to be 
somewhat greater, and extends in some instances to 17 or perhaps even 20 
fathoms. We should also remember that there abound on all coral reefs 
numberless organisms whose only role seems to be to cement again the 
particles and fragments broken by the action of the sea or of boring 
animals, and they play a most important part in forming coralline lime- 
stone full of reef building corals, which yet have nothing to do with the 
increase of thickness of the reef from their own growth. Nullipores, 
Algze, Corallines, Foraminifera, the minute fragments of corals or small 
particles of sand, all continue to act as great cementers at considerable 
depths far beyond that at which reef building corals have ceased to 
flourish. They act not only on the surface of the reef in the interior of 
the lagoons, but along its sea face and down to a considerable depth, 
and all along the outer slope they cement the fragments of corals 
which have fallen at the foot of the growing reef, and gradually trans- 
form the material of the talus into a hard limestone similar in its 
constitution to that of the reef building corals. But in this lime- 
stone formed of talus material, the corals no longer retain their natural 
attitude as when growing. It is a breccia of corals or a puddingstone, 
consisting sometimes of huge masses which have fallen from the 
growing face of the reef and rolled upon the talus along the sea 
slope where such a conglomerate breccia or puddingstone has been 
formed, and it reaches the depth of from 15 to 20 fathoms. Corals 
can again grow upon this buttress, and thus we may imagine the 
reefs of the present day to build outward and increase in thickness. 
This was the result which was hinted at from an examination of the 
sea face of the reef off Honolulu made in 1888.1 Of course I do not 
deny that some reef builders may occasionally live at greater depths than 
those I have mentioned, but their casual occurrence at those greater 
depths would not materially affect the growth in height and increase in 
width of the great majority of coral reefs ; and it is well known that 
Oculina, Lophohelia, and other genera, may cover extensive tracts at 
depths far beyond those at which so called reef builders flourish.’ 

1 Bull. Mus. Comp. Zodl., Vol. XVII. No. 3, April, 1889, p. 121. 

? Pourtalés, Mem. Mus. Comp. Zodl., Vol. II. No. 2, 1871; Wyville Thomson, 


Depths of the Sea, 1873, p. 482; also The Voyage of the Challenger, the Atlantic, 
1877, Vol. I. pp. 266-273. 


88 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


ISLANDS PARTLY VOLCANIC, AND PARTLY COMPOSED OF 
ELEVATED LIMESTONES. 


Kimbombo. 
Plates i9, 61. 


The Kimbombo Islets (Plate 61) are a group of three small islands, 
one, the highest, of volcanic structure ; the other two, the northern 
islets, are composed of elevated limestone, situated in the axis of a tri- 
angularly shaped lagoon, with twelve fathoms of water. The reef flat 
surrounding the lagoon is continuous, except at the northwestern 
point, where there is a passage into the lagoon (Plate 19). In ad- 
dition to the islands there are a number of coral patches and _ iso- 
lated rocks along the inner edge of the reef flat and in the west- 
ern part of the lagoon. The atoll is nearly five miles in its greatest 
length, and the southern face is about three miles long. As we did not 
enter this lagoon, I could not satisfy myself regarding the structure of 
all the outlying rocks on the outer edge of the submarine platform, 
some of which were evidently volcanic, others of elevated limestone. 
This is an interesting group, showing how varied the structure of an 
atoll may be, and yet the record on the chart be most deceptive, the 
substructure of the Kimbombos being volcanic at one extremity, and 
consisting of elevated limestone at the other. Half way from Kim- 
bombo to Ngillangillah Island rises the small peak of Trigger Rock to 
within four fathoms of the surface; to the east of the group lies Bell 
Reef, to the north Williamson and Dibble’s Reefs, and Lookout Reef still 
farther to the east, all separated by deep channels and rising abruptly 
from deep water. The substructure of these reefs is of course unknown, 
and may be either volcanic or limestone elevated or eroded to within a few 
fathoms of the surface. 


Exploring Isles. 
Plates 19, 19°, Figs. 1-3, and Plates 72-76. 


We entered the atoll of Vanua Mbalavu, or the Exploring Isles, as it 
was called by the United States Exploring Expedition in 1540, through 
the Ngillangillah Passage. The reef enclosing the islands is triangular 
in shape; its greatest length is over 22 miles along the sontheastern 
face; the breadth from the southeastern to the northwestern horn is 20 
miles. The outer reef flats are comparatively narrow, except in a few 
places where, near the islands of Munia, Malatta, and Susui, they pass 


ee ee Pe 


Ag at sia ——Ao — 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 89 


into the fringing reef flats. There are two important passes on the 
southeastern face,’ the Tongan and the American Passages. The latter 
is a narrow tongue of the ocean cutting into the eastern face of the 
slope of the atoll with over 100 fathoms in depth, and opens into a 
wide deep submarine valley extending westward into the heart of the 
eastern lagoon. The Tongan Pass is a similar, but much shallower and 
shorter, tongue of the ocean. On the western side the Andiwathe Pass 


NORTHEAST POINT OF VANUA MBALAVU. 


leads into a long deep lagoon formed by the outer reef and the west 
coast of Vanua Mbalavu. This western lagoon is connected on the 
south with the principal lagoon to the east of the island by a narrow 
and shallower passage over the fringing reef north of Malatta Island, 
and on the north by the passages leading round Ngillangillah Island into 
the passage of that name opening through the northwestern horn of the 


VANUA MBALAVU, LOOKING WEsT. 


outer reef, and which extends, gradually widening eastward, along the 
northern shore of Vanua Mbalavu until it opens beyond Avea Island 
into the large eastern lagoon. Along the northern face of the lagoon 
are situated Avea and Sovu Islands. About two miles from the 


1 An exception to the usual rule, that entrances to lagoons are on the lee side. 


90 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


eastern face is the island of Thikombiai lau. On the southern face are 
Ngillangillah, then follows the principal island of the group, Vanua 
Mbalavu, the western shore line of which is hollowed out by a deep 
indentation forming the western lagoon. Off its southern extremity is 
situated Malatta, next Susui, and finally the volcanic island of Munia. 
Vanua Mbalavu is fourteen miles long, forming a sharp angle at its 
highest and broadest point, where the island is nearly three miles wide 
and reaches a height of 930 feet. 

The central and highest part of Vanua Mbalavu is volcanic, but 
towards the northeast and the south the volcanic rocks have lifted up 
an ancient elevated reef which extends from opposite Avea westward. 
The volcanic rocks (Plate 72) dip very rapidly to the north, so that 
less than half way from Koro Mbasanga to Blackswan Point the bluffs 
are elevated limestones. These bluffs are deeply undercut, their surface 
pitted and thoroughly honeycombed, and full of potholes. The extent 


ISLET OFF NGILLANGILLAH. 


of the wearing of this coral rock is well shown by the deep bays and 
numberless indentations which characterize the northern coast of Vanua 
Mbalavu. When we come to the vicinity of Blackswan Point, the 
denudation and erosion of the elevated limestone has reached its 
maximum. Off the end of the large island lies the little island of 
Ngillangillah (Plate 73), which is entirely composed of elevated lime- 
stone, which here attains a thickness of 510 feet. Beyond Ngillangillah 
there are numerous negro-heads and coral patches, some of them 
being of considerable size; they are of ancient coral rock. The coral 
heads and negro-heads extend along the whole length of the outer reef 


AGASSIZ: FIJI ISLANDS AND CORAL’ REEFS. 91 


flat as far as we followed it to Avea. ‘The bluffs forming the steep 
sides of the island are undercut and deeply indented, forming gorges 
and ravines (Plate 74) which cut into the island or separate dome-like 
islets from the adjacent shores. The elevated limestone is full of species 
of coral, mainly large heads of species of Astreeans, of Mzeandrinas, and 
Pocillopores, which appear to be closely allied if not identical with those 
now living. One of the points of Ngillangillah was merely a thin shell 
covering a huge cavern some 90 feet in diameter and rising to a height 
of nearly 100 feet, and fall of stalactites. The rock in the pool at its 
base was covered with Gorgonians and small corals, and abounded in 
Comatulee. 

The narrow channel lying between the north shore of the large island 
and the outer reef is full of flourishing coral patches. The many nar- 
row deep cations (Plate 74) cut into the face of the island with the 
dome-shaped or mushroom-shaped heads of elevated reef rock projecting 
a few feet above the water line give to this shore line a very picturesque 
appearance. It isasimple matter to follow the extent of the elevated 
reef rock eastward, and to trace the gradual appearance of the central 
ridge of volcanic rocks until we come to the headland north of Koro 
Mbasanga (Plate 72), where we find only a comparatively small outlier 
of the elevated limestone, and a similar one to the south of the village. 
Northeast of Koro Mbasanga lies the island of Avea (Plate 75), which 
rises to a height of 600 feet, and which is wholly composed of elevated 
limestone. ‘This island as well as Susui runs at an angle from the 
outer reef, and shows the great width of the former elevated reef. From 
Koro Mbasanga south and for some distance beyond Lomaloma the vol- 
canic rocks occupy the whole width of the island, and the elevated lime- 
stone has disappeared to reappear again on the southern spit of the main 
island, and to extend eastward in the islands of Malatta and of Susui 
and their many outliers, as heads, rocks, and islets, both on the northern 
and off the eastern point of the latter island. The island of Munia 
consists, like the central part of Vanua Mbalavu, of voleanic rocks. The 
island of Thikombia i lau, on the contrary, is composed of elevated lime- 
stone rising toa height of 550 feet. Beyond Avea lie the Sovu Rocks, 
three small islets about two miles inside the outer reef, also of elevated 
limestone, one of which rises to a height of 230 feet. Between Avea 
and the Sovu Islets runs southerly for a distance of nearly five miles a 
series of narrow coral patches, which, so far as I can judge, are rem- 
nants of the ancient elevated limestones, as are probably the heads and 
patches of the eastern part of the lagoon beyond the Tongan Pass. On 


92 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


the contrary, many of the heads lying off the central parts of the east 
coast of Vanua Mbalavu are undoubtedly of volcanic origin, and are 
merely covered with a thin veneer of growing corals. Some of the small 
voleanic rocks and islets off the east central part of the east coast of 
Vanua Mbalavu are deeply undercut and eroded into mushroom-shape. 
By far the finest example of marine erosion of volcanic rocks is seen on 
Plate 62, which represents an eroded shore line with mushroom-shaped 
rocks off the shore, indicating a slight recent elevation. Plate 62 is 
taken from a photograph given us by Mr. E. G. Jones, and taken in Lau; 
unfortunately I am unable to state the exact locality. The islets of Yanu 
Yanu forming the harbor of Lomaloma consist of a yellow volcanic mud 
full of rounded pebbles, and some of the spits of the east coast of Vanua 
Mbalavu are composed of bedded volcanic mud (soapstone) similar to 
that found at Suva and its vicinity. The condition of the islands and 
islets and rocks, both of those composed of elevated coral reefs and of 
voleanic rock, clearly indicates the great denudation and erosion which 


VOLCANIC HILLS BACK OF LOMALOMA. 


have taken place, to leave only such fragmentary remains of the land 
which must have once occupied the area of the lagoon. It is possible 
that the age of the elevated limestone found at so many points in Fiji 
may be comparatively great, and that the ancient limestone forming the 
substructure of the reef of the present day may have been deposited in 
late tertiary times, immediately before the present epoch.’ 

As has been observed, the dip of the lagoon is to the eastward, or 
rather, in a general way, toward the slopes of the deep tongue of water 
forming the American Passage (Plate 19). This would seem to be the 
natural result of the elevation of the great flat of tertiary limestones 


1 See the report of Dr. Dall, referred to in another part of this Bulletin. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 93 


occupying the area of Vanua Mbalavu Lagoon, caused by the uplifting 
of the ridge forming the crest of Vanua Mbalavu, which has a short 
western slope and a long comparatively easy eastern slope, with the 
resulting deep valley leading to the American Passage, and perhaps a 
secondary elevation caused by the rising of Munia Island. 

The depth of the western lagoon varies between 10 and 20 fathoms, 
that of the western part of the eastern lagoon from 6 to 30, while the 
eastern part of the lagoon slopes gradually from 20 or 25 fathoms toward 
the 100 fathom tongue in the eastern face of the outer reef. On sound- 
ing one mile north from the edge of the outer reef, off Blackswan Point, 
we found, at 203 fathoms, hard bottom. The character of the bottom 
of the lagoon varies greatly according to its proximity to shores or 
heads or patches composed of volcanic rocks or of elevated coralliferous 
limestone, or of a combination of both. 

Nowhere in Fiji have we found the fringing corals growing in such 
profusion as in the Ngillangillah Channel. While steaming along the 
northern face of the reef, close to the outer edge, we had a good oppor- 
tunity to note the appearance of the outer reef flat, of a yellowish green 
color covered with patches of violet, indicating the areas incrusted by 
living corals. Being on the lee side, there was scarcely a ripple along 
the outer edge, which was in sharp contrast to the very dark blue of 
the water covering the outer slope of the reef, while on the inner side 
there was a more or less wide light greenish belt bordering the reef flat 
and passing through light blue into the darker blue of the narrow con- 
tinuation of the Ngillangillah Passage, itself dotted with greenish or 
yellowish patches of coral all along the reef flat, and on many of the 
inner patches were scattered negro-heads, consisting of elevated coral- 
liferous limestone. 


Mango. 
Plates 19, 22°, Fig. 3, and Plates 85-87. 


Mango is a circular island, the southeastern and southern faces of 
which consist of a rim of volcanic rocks, through which rises to a 
height of 670 feet the central elevated ridge of the island (Plate 19). 
On the northern and northeastern faces an ancient coralliferous lime- 
stone has been elevated to a height of from 200 to 300 feet or more. 
That part of the elevated limestone which lies across the break of the rim 
of the island has been eroded and denuded to form a small lagoon or 
diminutive sound (Plate 85). The entrance is flanked by low conicai 
or dome-shaped mounds and patches deeply undercut, some of which are 


94 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


mushroom-shaped. A passage has been cut for boats through the shal- 
low opening connecting the lagoon with the inner sound, which receives 
the drainage of the interior of the depressed basin. The elevated lime- 
stone bluffs extend from the northern horn of the rim, along the coast 
line, towards the landing place on the north face of the island. To the 


MANGO, SEEN FROM THE NORTHEAST. 


east of this, on the north shore, are fine blufis of elevated limestone, 
weathered into dome-like lamellar masses, with rounded masses and 
mushroom-shaped heads at the base (Plate 86). A little farther west, 
on the beach beyond the bluffs, the underlying volcanic rocks crop out 
again, and from there south the negro-heads on the western reef flats 
are all of volcanic origin. 

The island of Mango is almost circular, about three miles in diameter, 
surrounded by a barrier reef, which passes into a fringing reef off the 
northern coast near the landing, 
and off a part of the southeastern 
face of the island. The inner 
lagoon is very narrow, not more 
than a quarter of a mile in width, 
and also very shallow. Its great- 
est depth is about two fathoms, 
and it is further studded with 
negro-heads and coral patches, 
thus protecting the lagoon to a 
certain extent from the invasion 
of the sea. The ridge of elevated 
coralliferous limestones on the 
west side of the island extends 
as far as the first islet on the 
south face of Mango. There the 
central volcanic ridge which has raised the reef joins the western edge 
of the rim of the island. The ridge runs in a southerly direction, at a 


MANGO LANDING, VOLCANIC SUBSTRATUM. 


“ 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 95 


slight angle with the west coast ridge, and is separated from it by a deep 
valley. The three islets off the western part of the southern face of 
Mango are all on the outer edge of the reef flat (Plate 87). They con- 
sist of volcanic rocks. The central 
islet is the largest, and is com- 
posed in part of stratified volcanic 
mud underlaid by harder rocks. 
Between the islets, and extending 
over the outer reef flats to the 
north and to the east, stretch 
numerous negro-heads of a vol- 
canic nature. 

The island of Mango is of the 
same type as Fulanga, except that 
the erosion and denudation of the 
lagoon has not been carried on to 
so great an extent, Mango being 
composed so largely of harder 
voleanic rocks. The platform 
forming the reef flat is dug out into a very narrow and shallow lagoon, 
and both are studded with negro-heads, the remnants of the adjacent 
shore slopes. The inner sound, which in the case of Fulanga has been 
eroded and denuded to form a large inner basin, consists in Mango only 
of a diminutive basin studded with elevated limestone heads and rocks, 
and barely connecting with the exterior eastern lagoon ; the sea has not 


WEST OF MANGO LANDING, VOLCANIC 
SUBSTRATUM. 


found its way to any extent through the elevated limestone barrier lying 
across the break of the rim of the island. 


Lakemba. 
Plates 19, 21. 


The island of Lakemba is elliptical, with a prominent spit extending 
off its southern face. Its greatest diameter is about five miles and a 
half. The central mass of the island, which rises to a height of 720 
feet, is volcanic ; on the flanks of this, on the northwestern and western 
sides, are found nearly vertical steep shore bluffs of coralliferous lime- 
stone elevated to a height of from 200 to 250 feet. The ridges extending 
along the south shore, separated by a spur from the central mass, also 
consist of elevated reef rock. Lakemba is surrounded by a fringing 
reef, narrowest off the northwestern point of the island; it widens 


96 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


towards the south off the west coast, and on the eastern face of the 
island it attains a width of nearly a mile. In continuation of the 
fringing reef off the northern face and off the southern spit of Lakemba 
extends a narrow outer reef, enclosing a lagoon, irregularly rectangular 
in shape, about five miles in length. The lagoon is thickly studded 
with patches and heads; its greatest depth is 14 fathoms; on the east 
face of the outer reef there is a passage for steamers. This is another 
exception of a lagoon entrance on the windward side. It should, how- 
ever, be noted that the east face of the Lakemba atoll is protected to 
some extent by Aiwa and Oneata. 

The resemblance in shape of Lakemba and Kanathea, the latter of 
which we did not visit, is very marked. The encircling reef of the latter 
surounds a larger lagoon ; there is also a narrow extension of the lagoon 
on the south side of Kanathea, and a boat passage on the east face. 
One mile and a half south of Kanathea, and separated from it by a 
channel with a depth of 131 fathoms, lies the small summit of Morse 
Reef; and off the central part of the northern face of the encircling 
reef, Boehm Rock. At Lakemba Gardiner? has noticed the flat lime- 
stone hills which rise abruptly to a height of 60 to 70 feet on the west 
coast. the foundation being volcanic conglomerate, which forms the rest 
of the island. Captain Wilson states that on the reefs of the extreme 
south some of the islets are limestone, others volcanic, and he considers 
the three larger islands in the centre to be the remnants of an old 
crater. 


Thithia. 


Plate 20. 
I am informed by Bishop Vidal of Levuka that the island of Thithia, 
which we did not visit, is also composed in part of elevated limestone, 
in which large caverns have been excavated similar to those we saw in 
Ngillangillah Island. It is also stated by others to be in part volcanic. 
It resembles Mango in outline, appearance, and structure, but is some- 
what smaller; the fringing reef surrounding it is narrow. The central 
part of the island is probably a volcanic ridge, which has elevated the 
ancient limestone surrounding it. 


1 Loc. cit., p. 466. 


i 


: om 
r 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 97 


2 Naitamba. 
Plate 19. 


The cliffs of the southeast side of Naitamba consist of voleanic con- 
glomerates or puddingstone, which extend along the highest points of 
the ridge on that side of the island. But on the northern side of the 
island the ridge, rising to a height of over 100 feet, is clearly seen to 


NAITAMBA, FROM THE EAST. 


be composed of elevated limestone. Naitamba is surrounded by a 
narrow lagoon (Plate 19), which is a little over half a mile wide off 
the north side of the island, where its greatest depth is seven fathoms. 
On the southwest side the lagoon is very shallow and narrow, the reef 
becoming practically a fringing reef. The highest point of Naitamba 
is 910 feet. 


Mothe. 
Plate 22. 


The Mothe group is interesting, consisting of a volcanic island, Mothe, 
and of Karoni, a low island to the south of it, formed by a short ridge 
of elevated limestone rising to a height of 120 feet. An outer reef flat 
surrounds both the islands. It runs at a distance of a little over balfa 
mile from the shore of Mothe itself, which is also surrounded by a very 
narrow fringing reef. In that part ; 
of the lagoon there is only from two We Ama?) 2 
to five fathoms of water, and the: a 
channel is studded with heads. 

The lagoon enclosed by the Mothe Reef is shaped like a boot, the foot 
reaching towards the east and the leg in a northwesterly direction. 
Mothe Island is elliptical in outline. Its greatest diameter, running 
north and south, is about two and a half miles, and it rises to a height 
of 590 feet. There are only boat passages into the lagoon through the 
eastern face. Although these passages are on the eastern face, yet they 
are practically to the lee, owing to the westerly trend of the lagoon and 


VOL. XXXIII. i 


KARONI. 


98 ’ BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


the projection of Na Potu on the south. The deepest part of the lagoon 
is in the eastern point. It is only nine fathoms, and north of Karoni 
not more than seven. Na Potu, as the eastern point of the lagoon is 


NORTHWEST POINT OF MOTHE. 


called, is studded with rocks and heads. Off the northwestern point of 
Mothe we could distinctly see that the negro-heads rising upon the plat- 
‘ form of the outer reef flats were of volcanic origin. Mothe resembles 
in shape Lakemba and Kanathea. 


Kambara. 
Plates 22, 22°, Fig. 2, and Plates 77-79. 


Kambara Island is elliptical, nearly five miles in length, witha great- 
est breadth of three (Plate 22). It is surrounded by a rim of ele- 
vated limestone enclosing a depressed basin. The rim has an average 
height of between 300 and 350 feet, with steep cliffs on the sea face 
(Plate 77). On the northwest face of the island, near the village of 
Tokalan, the elevated limestone ridge is broken through by a conical hill 
470 feet high, which is of volcanic origin, and the flanks of which underlie 
the elevated limestone ridge resting on its sides (Plate 78). From this 
makes out a flat covered with negro-heads, all of volcanic origin, and of 
rocks similar to those of the high hill, while on each side the flats are 
covered with negro-heads composed of elevated limestone; on both 
grow very flourishing coral patches, and both are steep to, the reef flat, 
passing rapidly into deep water, plainly showing that the corals have 
had no share in shaping either of these slopes, the one composed of vol- 
canic rocks, the other of elevated coralliferous limestone.’ The island is 


1 Throughout Fiji we found along the cliffs and sea face of limestone islands 
masses of the red earth so characteristic of the denuded limestones of the Bahamas 
and Bermudas, as at Kambara, Ngillangillah, Yangasd, Oneata, Ongea, and other 
islands. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 99 


surrounded by a fringing reef which ends beyond the northern point of 
the island along the base of the vertical cliffs between it and Tokalau 
village (Plate 78), and becomes the merest thread to the south of it 
for a short distance. Along the rest of the west face there is a narrow 
incipient lagoon studded with coral patches, with from one to two 
fathoms of depth in places between the outer reef and the shore. 

Gardiner? describes the interior plateau of Kambara as being about 
100 feet above the level of the sea, and that ‘on the plateau itself are 
many small hills, rising nearly to the level of the rim, with very steep 
walls, and some springing almost like buttresses from the rim itself,” 
and that on this plateau there are a number of deep holes in which salt 
water is found and tidal influences are felt. This description corresponds 
with what has been observed in the zeolian hill basins of the Bahamas 
and Bermudas, in which atmospheric agencies are at work to form the 
incipient sounds, and finally the great sounds or lagoons of the islands 
of these groups. 

Gardiner? reports that the hills of Thikombia i ra are certainly of 
limestone, and at a distance appear distinctly terraced. 


SUNDRY ATOLLS. 


Pitman Reef. 
Plate 18. 


Pitman Reef is an oval atoll about a mile in greatest length. We 
passed within a cable’s length on the west side, and could see the outer 
edge of the reef flat uncovered at points, and patches of corals growing 
upon it. The reef flat seems to be 300 to 350 yards in width. It is 
widest at the northern extremity. The lagoon is marked on the chart 
as being eighteen fathoms deep. 


Motua Levu and Motua lai lai. 
Plate 18. 

Motua Levu and Motua lai lai are two atolls to the eastward of Lau- 
thala reef. The former is somewhat rectangular, about two miles in 
length, and encloses a lagoon with a greatest depth of twenty-five 
fathoms. On the northwest edge boats can cross into the lagoon. The 
latter is nearly circular, a mile in diameter, enclosing a small lagoon. 


1 Loe. cit., p. 464. 2 Loc. cit., p. 462. 


100 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


The yellowish reef flat is widest at its two extremities ; the coral patches 
appear to be very flourishing, and a few large negro-heads of coral pro- 
truded upon the inner edge of the reef flat. From its diminutive size, 
the whole atoll can be taken in at a glance, and it forms an excellent 
specimen of its kind (Plate 112), with its broad yellow reef flat edged 
on the outside by the white line of breakers separating it from the 
deep blue water, the inner edge passing from yellowish to light green, 
then to light blue, and finally to the darker blue of the central part of 
the lagoon. 


Williamson Reef. 
Plate 19. 


We passed close to Williamson Reef, which is a somewhat rectangular 
reef flat widest at the eastern face. The greater part is dry at low water, 
and encloses a lagoon with thirteen fathoms. The greatest length of the 
reef is a mile and a quarter by nearly a mile at its greatest width. 


Bell Reef. 
Plate 19. 


Bell Reef is separated from the Kimbombo cluster by a channel of 
nearly three quarters of a mile in width. It is irregularly triangular, 
with a reef flat of over half a mile in width. The reef flat of the western 
side is open. The sea breaks heavily on the eastern face, but there is 
little sea on the western face. The greatest depth in the lagoon is 
thirteen fathoms. 


Adolphus Reef, 


Plates 18, 22°, Figs. 16, 17. 


We steamed close to the eastern edge of Adolphus Reef. The outer 
rim is somewhat rectangular in outline, with rounded corners, and 
carries from one to four fathoms of water, enclosing a lagoon twenty 
fathoms in depth. It can be entered from the southwestern angle. 
We could not examine it, as the sea was breaking heavily upon it. We 
could, however, clearly distinguish the patches of corals growing inside 
of the breakers. 


These atolls are excellent examples of the effects of submarine ero- 
sion upon areas of different dimensions, ranging in size from Pitman 


—_ 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 101 


Reef to Motua lai lai, Motua Levu, and to Adolphus Reef. They all 
owe their origin to the disappearance through atmospheric agencies of 
the peaks or ridges of greater or less heights which they represent, and 
to the formation of lagoons by submarine erosion, passing finally into 
such sunken banks as the Penguin, Alexa, and other banks discovered 
by Captain Field in the “ Penguin,” and figured in Admiralty Chart 
1431 (see Plate 23*).. Possibly, as I have suggested in the case of 
the smaller atolls, the lagoons may represent the extinct craters of 
small volcanoes of which the rim has been planed off by the action 
of the sea. 

We did not visit Duff Reef (Plate 18), which, judging from the chart, 
presents no points of special interest or of difference, except in shape, 
from such atolls as Wailangilala. 


Thakau Momo. 
Plates 34, 12, 14, 233, Fig. 6. 


On our way from Nairai to Moturiki Channel we examined the Horse- 
shoe Reef (Thakau Momo) about nine miles northwest of Nairai. Owing 
to the high stage of the tide we did not find it awash, and could 
only trace the very narrow ring of the yellowish green flat upon which 
violet patches of corals could be seen dotted over its surface. This flat 
being edged on the outside by the narrow white rim of breakers, and 
the dark blue water of the deeper soundings on the inner edge being 
fringed by a narrow belt of light green passing into light blue and into 
the somewhat darker blue water of the central part of the lagoon. 

The plan of Thakau Momo (Plate 23%, Fig. 6) shows the narrow rim 
forming the outer edge of the lagoon awash, with a depth in the centre 
of twelve fathoms. The western edge is worn away, leaving the greater 
part of the rim of the lee edge more or less open to the outflow of the 
water pouring in over the weather edge. 


Tova Reef. 
Plate 23°, Fig. 5. 

The plan which is given of Tova Reef is more detailed, and shows a 
lagoon with a more complete rim than that of Thakau Momo, with boat 
passages on the lee side through the northern and western rim of the 
encircling reef. These two atolls are sharp peaks, the one, Thakau Momo, 
probably the summit of a volcanic ridge, the other, Tova, perhaps the 


102 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


summit of a peak of elevated coralliferous limestone, which have been 
denuded to the level of the sea and then subjected to submarine erosion, 
forming first a flat, then an incipient atoll of which the lagoon has been 
gouged out, in one case to twelve, in the other to sixteen fathoms. 
Upon the outer edge of the flats, corals have grown, protecting the rims 
to a great extent from further denudation and erosion. 

The depth of the plateau from which Tova rises is probably very 
considerable. The depth of water at a distance of seven or eight miles 
is, judging from soundings to the eastward, perhaps as much as 1,200 or 
1,500 fathoms ; while Thakau Momo apparently rises from a shallower 
depth of less than 500 fathoms to the north, and about 900 fathoms at 
a distance of about five miles. 

Such atolls as Thakau Momo, Tova, and a host of others occurring in 
Fiji, are identical in their mode of formation with such an atoll as the 
Hogsty in the Bahamas,’ the lagoon of which I believe to be due to 
mechanical causes similar to those which have shaped the above named 
Jagoons in Fiji. While the former are recognized by writers on coral 
reefs as true atolls, the latter are regarded as pseudo atolls. It is juggling 
with words to represent structures as different because the one is in the 
Pacific and the other in the Atlantic, and because the one is in an area 
recognized as stationary or as one of elevation, while the other is in an 
area formerly supposed to be one of subsidence and which is now found 
to be one of elevation. In both cases the coral rims of the atolls are 
shown to be of little thickness. The same authors refuse to recognize 
as true barrier reefs, and call them patch reefs, barrier reefs occurring 
in other districts than those examined by Dana and Darwin, because 
they have been shown to be of comparatively moderate thickness. We 
can now show, in the very districts which have been selected as typical, 
that neither the coral reefs of the atolls nor those of the barrier reefs 
have the thickness attributed to them. 


Thakau Lekaleka. 


Plates 21, 111. 


On our way from Oneata to Mothe we steamed: close to Thakau 
Lekaleka (Plate 21), a very narrow reef flat of polygonal outline, some- 
what more than a mile in diameter, enclosing a shallow lagoon, judging 
from the light blue color of the impounded water. The reef flat rises 


1 Bull. Mus. Comp. Zoél., Vol. XX VI. No. 1, p. 103, 1894, 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 103 


on the western edge of a bank sloping to the eastward, the 100 fathom 
line being more than half a mile from the eastern edge of the reef flat. 

A number of negro-heads, apparently coral, could be seen on the 
western horn of the reef flat. Plate 111 gives a good idea of the 
appearance of the curve of the narrow reef flat of one of these smaller 
atolls, with the sea breaking over the rim. 


LAGOONS OF ATOLLS. 


Dana denies that there is any connection between the channels of 
lagoons and prevailing currents, and asserts that the channels tend to 
be closed by the increase of growing corals. Certainly our experience 
in Fiji could not indicate such a conclusion, nor are the lagoons in the 
smaller islands without channels except where a closed ring of corai 
sand islets has accumulated on the outer rim,—a rare occurrence, 
and one where the Jagoon was formed while open to the influx of the 
sea. Some of the small islands, with lagoons which are dry, may be 
elevated islands reduced to that stage by atmospheric agencies. 

While there may be a large amount of coral ooze and mud deposited 
in the lagoon, yet even in the lagoons mentioned by Dana he states 
that the sea has access to them, and that they are remarkable for the 
salinity of the water and the absence of growing corals within the 
lagoon at high water.? 

Dana says ? that nine tenths of the atolls under six miles in length, 
half of those between six and twenty miles, and the majority of all 
atolls in the Pacific Ocean, have no entrances to the lagoon a fathom 
deep, and the larger part of those included in each of these groups have 
no open entrances at all. He further says that nine, ranging from 
one and a half to three miles in the larger diameter of the reef, have 
no lagoon, only a small depression in its place ; two of these take in 
water at high tide and the rest are dry (namely, seven), certainly 
a very small proportion, and that of diminutive atolls which give us 
little information regarding the formation of the larger ones. Surely we 
cannot reverse the process and let the formation of the large atolls 
precede that of the smaller, as is suggested by Dana,’ for in that case 
we should have around the small atolls the platforms or slopes which 
have gradually been formed by the filling of the larger lagoon as sup- 


1 Dana, Corals and Coral Islands, p. 182. 
2 Loe. cit., p. 300. 3 Loe. cit., p. 302. 


104 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


posed by him, and I know of no small atoll in which any such platform 
has been observed. 

Neither Dana nor Lendenfeld seem to take into account the mass of 
water which is poured into a lagoon, even if it has no boat passage, over 
the reef flat at low tide, to say nothing of the period during which the 
reef remains covered between low and high water times. 

A large atoll, like that of Ngele Levu, if it has been formed by 
subsidence, should be of greater depth. This has already been noticed 
by Admiral Wharton.t Ngele Levu is thirty-three miles round, grad- 
ually increasing in depth towards the western extremity from four to 
sixteen fathoms. It rises gradually from a ridge with a depth of about 
145 fathoms, and from a plateau of less than 400 fathoms in depth. 
There is no filling up of that lagoon; it is well scoured, and a strong 
current is constantly deepening the entrance and outlets at the western 
end, to say nothing of the mass of water which finds its way out over 
the reef flat. The lagoon of an atoll is often referred to by writers on 
coral reefs as a sort of stagnant pool, which must of necessity be grad- 
ually filling. Such is certainly not the case in the atolls with which I 
am acquainted, and it is the exception. If any one will take the trouble 
to examine the hydrographic charts of the coral reef regions, both in the 
Pacific and the Atlantic, they will find it to be the exception when the 
atoll of a lagoon is really impounded, or that of a barrier reef is shut 
out from a most active circulation carried on by the breakers rolling 
over the rim of the one and the barrier of the other into the enclosed 
lagoon. In Fiji, the only atolls which are enclosed and surrounded by 
a reef allowing no circulation or access to the sea are small, and play 
no part in the physiognomy of the reefs of the group, and I know of 
no barrier reef in Fiji the lagoon of which is not well threshed by 
the breakers, 

An examination of the charts accompanying this report will show on 
the rim of the larger atolls, both to windward and leeward, moderate 
depths, from one to three fathoms or less at innumerable places, forming 
a regular sieve of passages through which the breakers force their way. 
An examination of the charts will show the same results as regards the 
circulation across the barrier reefs of Fiji. Finally, we should re- 
member that at high tide even fringing reefs are washed in every part 
and scoured, and that, while at low tide a certain amount of stagnation 
in pools may occur, it is only temporary, and not the natural state of 
things. 

1 Nature, May 22, 1890, p. 81. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 105 


Lendenfeld } gives altogether too great prominence to the part played 
by dry atolls. They do not occur anywhere except as most diminutive 
atolls. The only atoll in Fiji which answers at all to the theoretic 
requisitions of Lendenfeld is that of Vuata Vatoa (Plate 23%, Fig. 4), 
near Turtle Island, in Lau. I have not visited the island, and my 
impression is taken from the chart” and the Sailing Directions where 
it is described. Yet even that atoll has outfalls on the northwest side, 
and the margin is awash at high water, evidently allowing large masses 
of water to be poured into the lagoon, so that further denudation and 
erosion must eventually so modify this atoll that there will be a larger 
and more open lagoon than formerly, and it will not fill up as is required 
from the other point of view. 


EXTINCT CRATERS AND ATOLLS. 


There is, however, still another phase in the formation of atolls 
which has received but little attention, and that is the influence of the 
denudation and erosion of velcanic summits or ridges, or of extinct 
craters, in the formation of atolls. There are in the Fijis two extinct 
craters which are most interesting. One of these is the small extinct 
erater of Thombia in the Ringgold Islands (Plates 18,70). The highest 
point of its rim, the exterior circumference of which is nearly two miles, 
is nearly 600 feet, and it is continuous with the exception of a small 
part of its eastern edge, about a fifth of a mile, across which a coral reef 
extends, the extension of the fringing reef surrounding the island closing 
the entrance to the crater; the enclosed basin has a depth of 24 
fathoms. The other extinct crater is that of the island of Totoya 
(Plates 16, 22, 66-69), an isolated peak in the southern part of the 
group. It is about six miles in diameter, with an inner basin of three 
miles in diameter and a depth of over thirty fathoms. The highest 
point of the rim is 1,200 feet, and at two points the rim is low, forming 
in one case a narrow isthmus separating the crater basin from the outer 
lagoon. The horns of the open rim are connected by a coral reef, over 
which thunders the Pacific swell, piling up the water into the great 
basin of the crater. This water finds its way out through an opening 
called the Gullet, which, though narrow, forms an excellent passage into 
the anchorage inside of the crater. This island has not only a fringing 


1 Nature, June 12, 1890, p. 148. 
2 Admiralty Chart, Plan 742. 


106 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


reef, but also a barrier reef of a triangular shape surrounding it. It is 
evident that this barrier has been formed upon the denuded and eroded 
spurs of Totoya, which once extended seaward from the outer rim of the 
volcano. 

Supposing, now, that the erosion of both Thombia and Totoya had 
continued for a period of time long enough to have reduced the rims of 
these volcanoes to the level of the sea, we should have, as soon as corals 
had covered the flats thus formed indicating the former existence of the 
rim, atolls of nearly circular form; the one with a circumference of only 
two miles, and a depth of 24 fathoms, without patches in the central 
lagoon; the other munch larger, more than 25 miles in circumference, 
having a depth of 34 fathoms inside the lagoon, which would be dotted 
with patches, some of them forming part of the rim, others being the 
remains of eroded spurs extending towards the centre of the extinct 
crater. 

Admiral Wharton? has given a most interesting sketch of Clipperton 
Atoll, in which he confirms the trachytic nature of the “ Rock ” of Clip- 


CLIPPERTON ROCK, 
(From a Photograph by J. T. Arundel.) 


perton, as determined by Professor Wolff? from specimens collected by 
Mr. Jensen and kindly sent me by Professor Davidson. The photo- 
graphs and specimens collected by Mr, J. T. Arundel, on which Admiral 
Wharton’s notice is based, have enabled him to give what seems to me 
a natural explanation of the character of the atoll. As he says, it is 


1 Quart. Journ. Geol. Soc. of London, May, 1898, p. 228. 
2 Bull. Mus. Comp. Zodl., Vol. XX VI. No. 1, p. 174, 1894. 


i a 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 107 


“‘the rare case of coral forming on the lip of a volcanic crater, one part 
of which alone, perhaps the plug, has resisted the action of the sea, 
which has worn the rest of it down to the limits of wave action.” 
The foregoing figure is a view of the rock (trachytic) rising to a height 
of sixty-two feet on the rim of the atoll. Admiral Wharton calls atten- 
tion to the great depth of this lagoon, perhaps fifty fathoms, as a depth 
not improbable if it be the crater of an extinct volcano. It would be 
most interesting to have Clipperton carefully examined and mapped. 
In the mean time, from its analogy with Totoya and Thombia, it seems 
to me that Admiral Wharton’s explanation is the only possible oue. 
We may perhaps add that the old rim may have also been subject to 
atmospheric denudation and erosion, in addition to being blown away 
in part during some eruption. 

There are in the Fijis a number of small atolls from one to three or 
more miles in circumference, the formation of which can also be satisfac- 
torily explained on the theory that they have been formed upon the 
eroded summits of extinct craters, reducing the rim of the volcano either 
to a continuous flat or to flats separated by deeper passages, as in the 
case of the low parts of the rim of Totoya, forming entrances into the 
enclosed lagoons. Such atolls are Motua Levu, Motua lai lai, the Adol- 
phus Reef (Plate 18), Bell Reef, Pitman Reef, Williamson Reef (Plate 
19), Horseshoe Reef (Plate 14), and Thakau Lekaleka (Plate 27), 
although it is possible that some of these atolls may have been formed 
from the submarine erosion and denudation of volcanic peaks or of 
elevated limestone masses. It is also possible that some of the larger 
groups in which volcanic islands are found, like Vanua Mbalavu (Plate 
19), Komo, Mothe (Plate 22), Lakemba (Plate 21), and Mbengha (Plate 8), 
may represent parts of the rims of extinct craters, the bulk of the vol- 
canic peaks having disappeared from erosion, and left the outer flats 
upon which the barrier reefs have grown, while the deeper valleys and 
gorges of these volcanic islands represent the undulations of the lagoons, 
which vary greatly in depth, reaching in the case of the Vanua Mbalavu 
(Plate 19) 72 fathoms in parts of the eastern slope of the lagoon. These 
great depths, far beyond any at which corals can grow, represent the 
elevated gorges of the slopes of the volcanic peak which probably once 
extended over the whole area enclosed by the outer reef, during the 
elevation of which the reef which once covered a part of the same area 
was lifted to its present or even a greater height. 

Such large volcanic centres with extensive craters of considerabl: 
depths are not unknown.. Haleakala (Plate 71) in the Sandwich 


108 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


Islands has a crater with a depth of nearly 450 fathoms, while many 
smaller peaks, some of fully 1,200 feet rise from its bottom, and its 
diameter is fully as great as that of many of the larger atolls of the 
Fijis. So that, at any rate in a volcanic district, the great depth of 
some of the atolls cannot now be considered as a proof of the theory of 
subsidence. 

A still larger extinct crater than Haleakala is that of Aso San in Japan, 
and in Java there are many craters of dimensions fully equal to those 
of a number of Fiji atolls. 

In addition to Thombia and Totoya, we found at Moala the rim of an 
extinct crater forming the deep bay on the east side of the island (Plates 
16, 56). The longest diameter of this crater must have been fully 
three miles, and had the denudation of the island been carried on some- 
what further, so as to eat away the low western rim of the crater (Plate 
56) and connect the deep bay of the east face (the extinct crater) with 
the indentation on the west of the island, it would be difficult to detect 


the existence of a former extinct crater from the narrow ridge or island ~ 


which would rise in the eastern part of the lagoon (Plates 16, 56). 

Kriimer? has attempted to account for the elongated outline of so 
many of the atolls of the Paumotu, Caroline, Marshall, Gilbert, and 
Ellice Islands, upon the theory that they owe their origin to submarine 
hot springs and volcanic eruptions, the material of which was distributed 
by the trend of the great oceanic currents in the general directions 
indicated by these island groups. 

While granting that volcanic agencies have raised the coral islands of 
the Pacific, we must remember that the shape of the islands and their 
extent are due to the size of the plateaus of submarine erosion which form 
the banks upon which coral reefs have grown. Undoubtedly the sub- 
stratum of many of the atolls may have been formed of volcanic ashes by 
eruptions similar to that which has thrown up Falcon Island, and which 
has been fully described by Lister.? Yet the great majority of the vol- 


1 Bau d. Korallenriffe, p. 88. 

2 J. J. Lister, A Visit to the newly emerged Falcon Island, Tonga Group, South 
Pacific. Proc. Roy. Geog. Soc., 1890, Vol. XII. p. 157. 

The island (Falcon) is composed of fine-grained dark grayish material, arranged 
in strata. “A bare brown heap of ashes round which the great rollers break and 
sweep the black shore in sheets of foam.” The eruption occurred four years ago; 
its present height is 153 feet. “ Considering how rapidly the island is being covered 
by the action of the waves, it is evident that in a few years .. . it will have disap- 
peared beneath the surface of the ocean. . . . Some distance to the east of it lie two 
islands, Namuka iki and Mango, and these islands have been elevated before any 


; 
. 
: 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 109 


canic islands which abound in the coral reef districts of the Pacific do 
not consist of such easily scattered material. In addition, it is well 
known that many of the islands are composed of elevated coralliferous 
limestones, and that is probably the composition of the substratum of 
many of the atolls of the Paumotu, Ellice, Gilbert, Tonga, and Fiji groups. 
They indicate the existence of more or less extensive submarine ridges 
composed either of limestone or of volcanic rocks, and not necessarily 
peaks or summits formed of volcanic ash and spread out by the action 
of the currents, as has been mapped out by Kramer.t Nor do we know 
enough of the configuration of the bottom to justify the statement that 
the atolls of a group are not separated by great depths such as separate 
the islands of the Samoan group. The soundings round Funafuti by 
the “ Penguin,” and others near Tonga and in Fiji (Plate 1), do not 
confirm Kramer’s views. 

The old view entertained by Chamisso regarding the mode of origin of 
the substratum upon which coral reefs are built does not greatly differ 


from that which we have applied to the formation of coral islands in 


Fiji. We have laid greater stress upon denudation and submarine 
erosion after elevation by volcanic agencies, while Chamisso? accepts 
the uplifting of the insular masses to the level at which coral begins 


to grow. 


considerable thickness of coral grew upon them. They are formed by stratified 
voleanie material deposited under water, and are now surrounded by broad coral 
reefs. In them we may read the possible future history of Falcon Island. If no 
elevation takes place, the stones and débris will give a resting place to a host 
of marine animals and plants, . . . and another fine island will be added to those 
summer seas.” Recent volcanic action in Tonga and in Samoa does not seem to 
have prevented there the formation of extensive coral reefs, as has been suggested 
by Dana. 

1 Loe. cit., pp. 95-97. 

2 “Wir denken uns eine Inselgruppe dieser Bildung als eine Felsenmasse, die 
sich mit senkrechten Wanden aus der unermesslichen Tiefe des Oceans erhebt und 
oben, nahe an dem Wasserspiegel, ein iiberflossenes Plateau bildet. Ein von der 
Natur rings um am Rande dieser Ebene aufgefiihrter breiter Damm, wandelt 
dieselbe in ein Becken um. . .. Er ist da Stellenweise unterbrochen und seine 
Liicken bieten oft selbst grésseren Schiffe Fahrenge dar. . . . Innerhalb dieser 
Thore liegen ofters einzelne Felsenbiinke. . . . Andere ahnliche Binke liegen hie 
und da im Innern des Becken zerstreut.” Kotzebue, Reise, Bd. III., Bemerkungen 
und Ansichten, 1826, von Adelbert v. Chamisso, p. 106. Chamisso gives an 
admirable account of Radack Ralick, and of the fauna, flora, and general aspect of 
this low coral island. 


110 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


VITI LEVU REEFS. 


Plates 1, 3, 5, 6, 7, 204, Figs. 9-12, and Plates 24-45. 


The great barrier and fringing reef which follows the southern and 
part of the eastern coasts of Viti Levu may be said to begin off the north- 
eastern extremity of the island of Ovalau (Plates 3, 7). Off that island 
a spur of the barrier reef extends in a northerly direction, terminating in 
deep water (Plate 3). From that point to off Tova Peak there is no 
barrier reef, the bottom being generally muddy, formed from the decom- 
position of the islets composed of soapstone, which are scattered in great 
number between Ovalau Island and the island of Viti Levu. Similar 
islands and islets abound along the shore of Viti Levu, and between it 
and the outer reef south of Moturiki towards Mbau and the Tomberua 
Passage (Plate 7). 

The islands of Viwa (Plate 36) and Mbau are both composed of 
stratified volcanic mud resting upon harder volcanic rocks, and the whole 
shore line of the adjoining part of Viti Levu is made up of the same ma- 
terial, judging by what we could see of the shore bluffs as we steamed 


FRINGING REEF HARBOR, OFF KORO LEVU. 


from the Moturiki Channel to Mbau. The soft rocks of the shores of that 
part of Viti Levu are readily disintegrated, and their erosion and denu- 
dation have supplied the material for the extensive mud flats (Plate 35) 
lying in the area just mentioned (Plate 7), leaving endless patches and 
small flats more or less covered with patches of growing corals. These 
softer rocks rest upon harder volcanic rocks, the extension of the rocks 
which attain a considerable height in Moturiki and a still greater one in 
the peaks of Ovalau." 


1 Both Ovalau and Moturiki are surrounded by a fringing reef. 


iM 


‘ 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 111 


The formation of the great barrier reef of the southern shores of Viti 
Levu is due to causes very similar to those which have given its present 
physiognomy to the northern coast of Cuba between Nuevitas and 
Matanzas. Along those parts of the island where denudation and 
erosion proceed rapidly owing to the soft character of the shore rocks, 
very extensive flats have been formed like those south of Ovalau. When 
the reef barrier flats have been eroded from a harder base, like volcanic 
rocks, the flats are less prominent; they are somewhat more extensive 
where the old elevated coralliferous limestone formed the shore hills; or 
the reef flats may disappear altogether when the harder volcanic rocks 
have been only little affected by erosion or denudation. From the na- 
ture of the negro-heads scattered upon the reef flats it is generally a 
simple matter to ascertain the character of the base of the reef flats of 
an atoll or of a barrier reef. 


: 


| 


4 


MOTURIKI CHANNEL. 


The islands of Ovalau and of Moturiki (Plate 7), which are enclosed 
by the northeastern extremity of the Viti Levu barrier reef, are both of 


ENTRANCE TO LEVUKA. 


volcanic formation, a kind of conglomerate or breccia similar to that 
found at Mbengha, Tavuki in Kandavu, and in many other places in 
Fiji. The highest peak of Ovalau rises to a height of nearly 2,100 feet, 


112 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


and the shape of its ridges, crests, and peaks (Plates 33, 34) shows the 
effect of extensive denudation and erosion. The island is elliptical, eight 
miles long, and about six wide. Moturiki flanks Ovalau on the southwest 
side, is low, about five miles long, and connected with the southern face 
of Ovalau by an extensive fringing reef flat surrounding its eastern face 
and the islands of Yanutha Levu and Yanutha lai lai. The Moturiki 
fringing reef is separated from the barrier reef by a narrow channel, and 
the northern extension, forming the barrier reef off the east coast of Ovalau 
(Plate 20°), is broken by a number of deep openings (Plate 7). The 
bottom of the lagoon is made up of coral and coralline sand, compara- 
tively little mud being washed down from the hill slopes, the water inside 
the lagoon being quite clear. From the inner edge of the barrier reef 
run out a large number of very flourishing coral patches in from two to 
three fathoms, and extending to seven or eight. The reef flat is in some 
places more than half a mile wide (Plate 20°, Figs. 1-5). A good many 


NEGRO-HEAD, LEVUKA BARRIER REEF. 


negro-heads are scattered upon the reef flats, some of them of consider- 
able size. The average depth of the narrow lagoon separating Ovalau 
from the barrier reef is from nine to fifteen fathoms, but in some places 
there are short stretches with a depth of from sixteen to twenty 
fathoms. 

Between the Na lulu and the Ngava Passages (Plate 7) an extensive 
flat connects the barrier reef with Ovalau, much as the fringing reef of 


7s 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 113 


Moturiki is connected with the barrier reef stretch opposite its eastern 
face. There is also a similar connection between the fringing reef off 
Bololo Point and the barrier north of Na lulu entrance. The south- 
eastern part of the reef off Ovalau and Moturiki being ‘strictly neither a 
barrier nor a fringing reef, but a combination of the two, the Ngava and 
Na lulu entrances forming reef harbors similar to those characteristic of 
fringing reefs, indicating how the offshore platform of Ovalau has been 
eroded and how corals have gradually obtained a footing on the un- 
derlying volcanic substructure, remnants of which are visible at many 
points of the barrier reef flats. One may judge of the extent of the 
denudation and erosion which have taken place from the shape of the 
peaks and bluffs and ridges which give to Ovalau so characteristic a 
profile when seen from the sea (Plates 33, 34). Compare the sharp 
peak of Tumuna, the rounded elevations forming the ridge of Ndelai 
and of Koro Levu, the sugar loaf of Craig, and the bluffs near Levuka. 


LEVUKA. 


The spur which has formed the island of Moturiki is covered by low 
conical hills, culminating on the eastern summit at Ului Mboa, which is 
but little higher than the rest of the island. 

To the westward and northward of Ovalau reach the extensive flats 
full of patches which connect the west shore of Ovalau with the mainland, 
and reach on the northwest to Tova and south towards Mban (Plate 7); 
flats which are formed by the disintegration of the low bluffs, consisting 
of bedded volcanic mud (“soapstone”), which must once have extended 
eastward close to Ovalau and Moturiki. The patches on the flats are 
covered with growing corals. 

VOL, XXXIII, 8 


114 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


The stretch of strata of volcanic mud constituting the east shore of Viti 
Levu north of Mbau undoubtedly once extended farther east, connecting 
the main island with the islands of Moturiki and of Ovalau. This readily 
explains the changeable character of the barrier reef at different points 
along the coast of Viti Levu. Off Ovalau and Moturiki the substructure 
of the barrier reef is volcanic, and the negro-heads which crop out upon 
its surface at various points plainly indicate this. One of the most 
striking of these protrusions being a small mushroom-shaped volcanic 
rock on the barrier reef to the south of Moturiki, immediately west of 
Thangalai Island (Plate 7). This island and Leluvia, and one or two 
keys on the northern part of the great reef south of Moturiki, are small 
islets of coral sand thrown up on some of the shallower parts of the reef 
flats. The larger islands are thickly covered with cocoanuts and shrubs. 
On the southern part of the reef flats immediately north of the Tombe- 
rua Passage near the exterior edge is the island of Mumbualau. It is 
about thirty feet high, and is composed of elevated coralliferous limestone 
deeply undercut, pitted, and honeycombed, while the islands farther 
inland off Kamba Point consist of stratified voleanic mud. 

Another very striking fragment of elevated coralliferous limestone is 
that of Na Vunivatu (Plate 37), ‘on the reef flats to the south of Nasilai 
Mouth. The remnants of the elevated reef can be traced south of Tom- 
berua Passage on the Nasilai reef flats, and extend on both sides of the 
lighthouse. There are numerous heads of elevated limestone, fragments 
of former large stretches of the same material. Still farther south the 
elevated coralliferous limestone is seen to underlie the island of Nukulau 
(Plates 38-41) at the mouth of Lauthala Harbor (Plate 25), as well as 
the flats to the eastward and the island of Mokaluva with its flat (Plate 
38). The extensive mud flats forming the mouth of the Rewa River 
have to a great extent encroached upon the inner edge of the coral 
reef flats underlaid by the elevated coralliferous limestone which every- 
where crops to the surface to the south of Tomberua Passage. As far 
as the Nukulau mouth of the Rewa, the reefs are in reality fringing 
reefs growing upon flats of elevated coralliferous limestone, intersected 
by deep indentations forming reef harbors. The great extent of the flats 
skirting the shore of Viti Levu eastward from Suva Point shows the 
amount of denudation and erosion to which this part of the island has 
been subjected (Plates 24,25). From off Lauthala Bay (Plate 25) to 
Suva, the reefs are extensive barrier reef flats separated by passages 
leading into the channel running between the barrier and the shore 
(Plate 7). Some parts of the barrier flats are more than a mile wide, 


al 


ce ee ee 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. LES 


The barrier reef flat north of Tomberua Passage and south of Rat Pas- 
sage is in many places nearly three miles wide, with an average width of 
about two miles. The wide reefs of Serua and of Rovondrau Bays 
(Plate 5) are covered with flourishing patches of corals; what their 
substratum is I am unable to determine from the absence of negro-heads 
on the outer reef flats. Judging however from the nature of the head- 
lands and of the rocks cropping out all along the shore between Serua 
and Suva, it is probably of the “ soapstone,” —the bedded volcanic mud 
so characteristic of the shores of Viti Levu both east and west of Suva, 
with the exception of a small key probably of elevated limestone on the 
end of Rovondrau Reefs (Plate 5). 

To the east of Namuka Harbor, a small reef harbor formed like the 
Navua and the Tongoro pass through the outer reef flats, and the elevated 
limestone again forms the substratum of the reef flats. The reef is here 
a fringing reef, which can be navigated by boats near the shore after half 
tide, and the outer face is covered with large negro-heads consisting of 
elevated coralliferous limestone. West of the entrance to Suva Harbor 
(Plate 5) the reef occurs in successive stretches of fringing or of barrier 
reef outside of fringing reefs, forming in some cases small reef harbors, 
like Namuka, Nanggara, Vatuloa, Navua, Serua, or, opposite the mouth 
of the Navua River, a large open bight, Rovondrau Bay. 

The passages through the Viti Levu barrier reef and its principal 
reef harbors, Suva among others, are generally opposite the mouth of 
some river or creek, through which considerable fresh water carrying 
silt flows ; this is especially the case of the Rewa River, which brings 
through its many mouths an immense amount of silt and detritus, and 
has formed a great delta. Both Darwin and Dana have attributed the 
formation of reef harbors largely to local currents, to the presence of 
fresh water, and to the action of silt. The bringing down of detritus, 
especially in the rainy season, and its deposition in channels will keep 
the bottom clear of corals, and thus form passages or reef harbors. 
The extensive reef which protects the harbor of Rewa has been formed 
in part by thé erosion of the softer volcanic beds, and in part by the 
deposition of the silt brought down by the Rewa and the cutting out 
of a barrier channel behind the reef. 

To the west of Serua the barrier reef disappears (Plates 5, 6), and the 
shore line is now composed of hard volcanic rocks which are not easily 
decomposed, or consists of the soft and easily disintegrated volcanic mud 
strata extending as a general thing from Mbau to Serua. Although 
here and there the harder rocks push out to the shore, where they are 


116 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


edged with a fringing reef, or we may find the remnants of the elevated 
coralliferous limestone, which is less easily eroded than the volcanic mud 
strata, as in the elevated reef in a valley to the north of Suva. This 
reef rises to a height of 120 feet above high water mark, and is fully 
fifty feet thick (Plate 31). Its extension can be traced in outliers on 
the north shore of Suva Harbor and on islands composed of elevated 
limestone at the mouth of the inner harbor of Suva, — islands which 
are from sixty to ninety feet in height, and rest directly upon beds of 
stratified volcanic mud and capped by similar strata. On the northwest 
shore of the inner harbor there is a bluff of the same elevated limestone 
rising to about sixty feet. The continuation of the reef can be traced 
inland and along the shore for a considerable distance. 

The character of the islands within the barrier reef patches of Namuka 
and of Serua indicate that the corals growing upon the flats rest upon 
beds of stratified voleanic mud (Plate 5). Here and there we find a 
negro-head of the harder volcanic rock upon which the voleanic muds 
rest. From Serua westward the fringing reef varies in width from a mile 
to a mere narrow fringe of corals close to the shore (Plate 42). Negro- 
heads of volcanic rock stud the reef flats, which are here and there 
hollowed out into small boat harbors (Plate 6). At the Singatoka 
River the fringing reef has disappeared (Plate 6), and the heavy 
breakers roll upon a coral sand beach for a distance of about three 
niles. Immediately behind the beach rises a line of huge coral sand 
dunes, one of which attains a height of 190 feet (Plate 44). At this 
point the character of the fringing reef changes again. It is built upon 
the remnants of the ancient elevated limestone reef (Plate 43), small 
bluffs of which occur all the way between the Singatoka River and 
Nandronga Harbor (Plate 45). Some of the bluffs on the shore 
attain a height of more than seventy feet. Negro-heads consisting 
of elevated limestone fragments now abound upon the whole line of 
the fringing reef, and the two islands which protect the harbor of 
Nandronga on the east, and on the west are outliers of the ancient 
elevated reef (Plate 45). The height (thickness) of that reef must 
have been very considerable, judging from the height of an extensive 
bluff, consisting of limestone to the north of the sand dunes at the mouth 
of the Singatoka, which must be fully 250 feet. The fringing reef 
extends to the west of Nandronga as far as Likuri Harbor, where it 
gradually passes again into a barrier reef with a gradually widening 
shore passage (Plate 6) as we approach the Nandi waters. 

The elevated limestone reef must have extended west as far as Viwa, 


. ae 


Peper: 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 17 


and north again as far as Asawa i lau, both of which islands, as I am 
informed by Dr. Corney, consist of elevated limestone (Plate 2). Viwa 
is 100 feet in height.? 


Plateau off Nandi and Yasawa. 


To the westward of Nandi waters (Plate 3), off the northwest coast 
of Viti Levu, extends a wide plateau, the result of the denudation and 
submarine erosion of that side of the island. The depth of this plateau 
is most irregular, varying from ten to forty fathoms. The plateau is 
studded with sunken patches, and with rocks and islets and islands. The 
southwestern line of islands from the Mololo Islands to Mana is flanked 
by an outer line of reef flats, which gradually become smaller and disap- 
pear off Tartar Reef (Plate 3). From these the edge of the plateau 
crosses toward the north, and the outer reefs reappear again to the 
westward of the long chain of the Yasawa group. 

The Viwa Island reef is separated by a narrow, deep channel, with 
137 fathoms in mid-channel, from the western edge of the Yasawa 
platean. To the northward of the Malolo Islands are scattered a few 
islands, — Kandavu, Lovuka, Tavua,and Vomo. The last is of volcanic 


VOMO LAI LAI. 


origin, while Kandavu is flanked by beach rock, as is also Tavarua at the 
entrance of Navula Passage. All the islands which Captain Thomson 
examined on his way from the Malolo Islands to Waia he found to 
be of volcanic origin,— Mana, Tavua, Monu, and others. As I have 


1 The elevated limestone patches which begin at Singatoka extend to the patches 
and reef flats north of Navula Passage (Plates 2, 3). Captain Thomson collected 


some pieces of a negro-head on the edge of the reef flat near Tavarua Island 
which consisted of elevated limestone. 


118 BUILETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


already stated, Viwa and Asawa i lau are said to consist of elevated 


limestone. 
The Malolo Islands rise to more than 700 feet. Mana is 240 feet 


NORTHERN END OF MANA. 


high, Mondriki and Monu respectively 590 and 730 feet, and Waia more 
than 1,800 feet. The extension northward of the Yasawa group forms 
a chain of sixteen high islands for a length of fifty miles, which ter- 
minates in the reef of the Kinsilk Islands on the south of Round 
Island Passage, the principal entrance through the Great Sea Reef off 
Vanua Levu. The Yasawa Islands, as well as the islands to the westward 
of the Nandi Waters, are,surrounded by fringing reefs. As will be seen 
from the charts, the reefs are on the western face of the plateau (Plate 3); 
so that the outer reef flats and the chain of inner islands intercept the 
full access of the sea, and corals grow but sparingly inside of that line. 


Suva Reef Flats. 
Plates 5, 24-30, 65, 76. 


Perhaps no reef flats illustrate better the grinding and wearing action 
of the sea than those of the barrier reef, both to the east and west of the 
entrance to Suva Harbor, All the inequalities of surface seem to have 
been levelled off as with a plane, leaving only the shallow pools formed 
by the interstices of the large masses of coral (Plates 28-30). The 
fauna of the surface of these reef flats is comparatively poor in species, 
but abundant in individuals. A large black Ophiothrix, with its disk 
hidden in some crack or corner, trails its arms in all directions, and they 
literally swarm in all parts of the reef. Towards the outer edge they 
are replaced by Echinometra lucunter, the holes and hollow ways of 
which, often over two inches deep, honeycomb the surface, leaving nar- 


~~ eee 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 119 


row walls to separate them (Plate 30); and finally, near the outermost 
edge begins the belt of Madrepores and Pocillopores (Plates 28, 29) 
which extends into the line of breakers and beyond. ‘There are few of 
the massive type of corals, like Porites, Astrea, and the like, and these 
are of diminutive size. 

The surface of the reef is kept from too rapid wearing by the growth 
of marine algze and of corallines which carpet it. The alge are mainly 
species of Udotea, of Caulerpa, and of Turbinaria, which in sheltered 
pools grow to a considerable size. One finds also on the surface an occa- 
sional large black Holothurian, a blue Linckia, a green Goniaster, a Mu- 
reena darting from a pool, a large Cancer trying to hide under a shelving 
piece of coral, or a Squilla, or a few specimens of small fish of a brilliant 
blue color. There are few Mollusks under the negro-heads and dead 
masses of coral scattered upon the reef; the lower surface of these is 
often carpeted with many species of brilliantly colored Sponges, in which 
small Mollusks, Crustacea, and Annelids find refuge. The coral masses 
themselves are perforated in all directions by boring Mollusks and 
Annelids. 

The substratum of the eastern and the western reef is made up of 
elevated limestone, extending from the shore close to the outer edge of 
the reef, independently of the thin crust of corals which grows upon the 
outer edge of the reef flat. So it is also with the musbroom-shaped heads 
which are found upon the outer edge of the reef flats of Vatu Leile, Mango, 
and other islands consisting wholly or in part of older limestones. They 
are all composed of the same rock as that of the shores and of the sub- 
structure. The outer sea face of the reef flats is steep in all cases, irre- 
spective of the increase due to the corals growing upon them, or of the 


character of the underlying rock, which is only an unimportant factor 


in determining the thickness of the sea face edge of the outer reef 
flats. 

We also examined the outer face of the barrier reef forming the east- 
ern edge of the passage leading into Suva Harbor. This reef flat, like 
that of the western side of the passage, is entirely made up of ancient 
elevated limestone planed down by the sea to a level flat, with small shal- 
low pools scattered over the surface. Negro-heads and fragments of the 
ancient limestone are scattered over considerable areas on the reef flat ; 
many of them have been thrown up by the sea from the undermining of 
the outer edge, others have been torn off from the reef flat itself, and both 
are gradually wearing away, leaving fragments of branches of corals and 
of coral heads scattered over the reef. The belt of the reef flat close to 


120 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


the line of breakers is riddled with holes and channels gouged out by the 
Echinometra common on the reef. These channels look like short wind- 
ing drill holes extending in all directions, or merely small potholes in 
which the Echinometre live protected from the action of the breakers 
(Plate 30). In the same belt corals begin to grow in greater profusion, 
mainly Pocillopores, Madrepores, and small heads of Astreans and of 
Goniastreans or Mezandrinas, a few of these are also found scattered 
on the inner part of the reef flat. The corals living upon the outer edge 
of the reef flat form merely a thin crust, between the patches of which 
the substratum of elevated limestone crops out. Similarly, at a great 
many other points in Fiji, the outer edge of the reef flat, when exposed 
at the very lowest stages of tide, is seen to be edged with a belt of rocks 
identical in structure to that which forms the substratum of the reef 
flat platform. I may mention Mango, Vatu Leile, and a number of the 
islands of Fiji which have been described. The slope of the outer edge 
of the reef flat falling off more or less rapidly has little to do with the 
recent reef crust growing upon it; that only modifies its slope, possibly 
to twenty fathoms. The general slope of the sea face of the reef is dne 
to conditions which antedate the formation of the coral reefs of the 
present day. 

Dana! says that beneath the channels (basins) lies in general the 
coral rock of the reef region, the inferior part of the great reef forma- 
tion, whose upper portious constitute the so called barrier and fringing 
reefs. This certainly is not generally the case: see the description of 
the flats between Ovalau and Mbau. Dana himself cites a number of 
examples which do not accord with his views when describing great” 
admixtures of coral and of material derived from the mountains adjoin- 
ing, and as he well says: ‘ When the materials from both sources, the 
shore and the reef, are mingled, the proportion will necessarily depend 
on the proximity to the mouths of streams, the breadth of the inner 
waters or channels, and the direction and force of the currents.” 

As has already been observed by Dana, “ At low tide the breakers 
often cease, or nearly so.”? It is frequently possible a short time before 
the turn of the tide to examine the corals growing on the outer face of 
a reef. At Komo we had an opportunity to photograph coral reef flats 
where the corals were growing upon a substratum of volcanic rocks 
(Plate 65) just as they are growing upon a basement of tertiary lime- 
stone at the entrance of Suva Harbor. At Ngillangillah we came upon 


1 Corals and Coral Islands, p. 149. 
2 Loc. cit., p. 131. 


—— 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 13k 


a fringing reef flat covered with Alcyonarians (Plate 76), similar to 
those figured by Kent. 

Gardiner has observed the important part which incrusting coralline 
alge perform in Fiji in supplying the material for a reef rock of compact 
homogeneous structure ; they undoubtedly assist materially in prevent- 
ing the disintegration of dead corals, and their subsequent commiuution 
by the action of the waves. In an interesting article on the calcareous 
alge of the Gulf of Naples,? Walther has given an excellent account 
of the part which coralline alge like Lithothamnium play in building 
up amorphous limestone deposits of considerable thickness from the 
obliteration of its structure.? But he has confused the theory of the 
formation of reefs with the theory of the formation of limestone deposits 
of great thickness, one of which is based on an assumption, the other 
which is not in the least open to doubt. It is evident, however, that 
those who have examined coral reefs have not attributed to coralline 
alge the share which they have in building up recent amorphous lime- 
stone deposits of considerable thickness. 

The following list of algee collected I owe to the kindness of Professor 
Farlow: Amphiroa fragilissima Lam’x ; Galaxaurafragilis Lam’x, var. 
fastigiata Decaisne; Liagora Preissii Louder, var. pacifica Grunow ; 
Padina Pavonia (L.) Gaillon ; Dictyata ciliata J. Ag. sterile ; Turbina- 
ria conoides Kg. ; Hydroelathrus cancellatus Borg.; Sphacelaria furci- 
gera Kg.? sterile; Caulerpa Freycenetii C. Ag.; C. clavifera (Turn.) 
C. Ag.; C. complanata J. Ag.; Halimeda macroloba Decaisne; H. 
Opuntia (L.) Lam’x; H. polydactylis J. Ag.; Aurainvillea comosa 
(Harv.) Murray & Boodle; Aur. papuana Murray & Boodle; Dictyo- 
spheria favulosa Decaisne ; Valonia egagropila (Roth) J. Ag.; Valonia 
utricularis J. Ag. 


ISLANDS AND CORAL REEFS DESCRIBED FROM THE CHARTS. 


With the exception of the Argo Reefs (Plates 19, 20), the islands 
and reefs we did not visit were insignificant in size, or, judging from 
the charts, presented no point of interest not included in those we ex- 
amined. I may mention among these Vanua Vatu (Plate 21), a small 
circular island with a depressed central summit, about a mile and a half 
long. It is composed of elevated coralliferous limestone rising to 310 


1 Loe. cit., p. 477. 
2 Zeitsch. d. deutschen geol. Gesell., Heft 2, Bd. XXXVIL, 1885, p. 329. 
8 See also an article by Fresh, Neues Jahrbuch f. Mineral., 1892, II. 169. 


122 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


feet. It resembles Naiau on a smaller scale. It is surrounded as is 
Tuvuthé by a narrow outer reef flat, becoming a fringing reef at several 
points of the shore, and enclosing a narrow and shallow lagoon full of 
rocks and patches. 

There are also a number of atolls presenting no special features. To 
the westward of Ngele Levu are two reefs, Thakau Vutho Vutho 
and Thakau Mata Thuthu (Plate 17). The former is separated from 
Ngele Levu by a channel eight miles wide, with 145 fathoms in mid- 


channel. The latter is separated from Thakau Vutho Vutho by a 


channel 171 fathoms deep and three miles wide. The lagoons have 
respectively a greatest depth of 15 and 19 fathoms. They both have 
navigable entrances, and the outer reef flats are studded with negro- 
heads and coral patches, and there are no islands on the rim. These 
atolls resemble Ngele Levu, but are not more than one third of its size. 

It is interesting to note that to the westward of Thakau Mata Thuthu 
(Plate 17) there is an isolated bank with 74 and 76 fathoms of water, 
but separated from it by a narrow channel; it may be a spur of the 
bank upon which the atoll of Thakau Mata Thuthu is situated, similar 
to Cock’s Bank, which is close to the southwestern edge of the 100 
fathom line. 

Similar atolls and varying greatly in shape are Duff’s Reef (Plate 18) 
to the west of Wailangilala, and to the south Dibble’s Reef (Plate 19), 
to the east of Vanua Mbalavu, Nuku Thikombia (Plate 19), and Male- 
vuvu Reef (Plate 19) ; farther south Thakau Tambu, Yaroua, and the 
smaller reefs Thakaun Nokeva and Thakau Lasemarawa (Plate 20). 
As we steamed from Tuvuthé to Naiau we saw the sandbank in the 
centre of Tavanuku i vanua Reef surrounded by a fringing reef somewhat 
more than a third of a mile in width (Plate 20). To the southwest of 
Tuvuthaé is also situated a small circular atoll, Tavanuku i wai, with 
an outer reef of about half a mile in diameter enclosing a small shallow 
lagoon. 

To the east of Mothe are Thakau Motu (Plate 22), a large atoll open 
to the west, with 24 fathoms in the deepest part of the lagoon (Plate 
23*, Fig. 6), and Thakau Vau (Plate 22), a small circular reef with a 
shallow lagoon of impounded water. Neither of these did we visit. West 
of Komo, Thakau Vuite (Plate 22), in a line running north and south, 
east of the Yangas4 cluster, lies Thakau Levu, and southwest of Vanua 
Vatu and to the northeast of Totoya the Tova or Na Vatu Reef (Plate 
23*, Fig. 5, and Plate 20%, Figs. 13, 14). Tova has been well surveyed 
(Plate 20%, Figs. 15, 14, and Plate 23%, Fig. 5) ; unfortunately we were 


: 
‘ 
p 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 123 


not able to visit it, but, as will be seen, it closely resembles the Horse- 
shoe Reef (Thakau Momo, Plate 23°, Fig. 6), which we examined. All 
these islands are atolls with an outer reef flat and a lagoon of moderate 
depth, varying from ten to about twenty fathoms as the greatest depth, 
with entrances into the lagoon, and with only rocks and patches and no 
islands on the outer reef flats. 

Thakau Vau, Thakau Lasermarawa (Plate 20), and Thakau Nawa en- 
close impounded water. South of Thakau Levu (Plate 22) are Thakau 
Thikondua, Thakau Reivareiva, Thakau Nasokesoke, and Thakau Teteika, 
representing probably as well as Wilkes Reef north of Namuka, and the 
two reefs Tavanuku i wai and Tavanuku i vanua and Frost Reef, the 
summits of small peaks or of crests, now covered only by heads on which 
corals have found a footing. In the case of Tavunasithi (Plate 22), Nuku 
Songea, Yaroua, Maafu Rock, and the Nukutolu Islets west of Yathata, 
the summits are still visible. Naiabo Islet is the remnant of a small 
island now surrounded by a very narrow outer reef flat enclosing a lagoon. 

We did not visit the Nukutolu Islets (Plate 19), which seem to be the 
summits of a former narrow ridge. Frost Reef, to the west of Mango 
(Plate 19), is a flat circular reef of about a mile in diameter, with a rock 
at its northern edge. 

Neither did we examine the following islands and reefs to the south 
of the Exploring Isles (Plate 19): Malevuvu Reef, an atoll nearly three 
miles long by half that in width, and a lagoon with thirteen fathoms 
greatest depth, accessible to boats on the west side; Katavanga, a small 
island, consisting, according to Captain Cocks, of elevated coralliferous 
limestone rising to a height of 180 feet, situated in the western part of 
the elliptical lagoon encircled by a reef flat widest at the eastern face, 
and over three miles in greatest diameter, with a greatest depth of thir- 
teen fathoms, and an opening for small vessels on the northern side of 
the lagoon; and Vekai, an elevated limestone rock nearly thirty feet high 
on the inner edge of a circular reef about two miles in diameter, with a 
boat passage on the northwest side leading into a lagoon with a greatest 
depth of eighteen fathoms. The Malima Reef resembles Kimbombo Reef. 
The islets are near the centre of a lagoon about two miles in diameter. 

It would not be difficult in most cases to determine how these smaller 
reefs have been formed. They are either in part volcanic and in part 
elevated coralliferous limestone, or wholly volcanic, or elevated limestone 
alone. The result would in either case be the same. The volcanic 
islets disintegrating more slowly than the tertiary limestone, it is prob 
able that the reefs, which show no signs of volcanic rocks, have a sul- 


124 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


stratum of ancient limestone of greater or less thickness, according to 
the height to which the particular reef has been elevated. 

An atoll formed from the disintegration, erosion, and denudation of an 
island of volcanic structure, like Komo, for instance, would not differ in 
structure from an atoll like Oneata, formed from the disintegration of an 
island composed of elevated coralliferous limestone; but their origin 
would at once be detected, if the islands had disappeared, from the exist- 
ence in one case of negro-heads and rocks of volcanic origin, in the other 
of coralliferous limestone scattered within the lagoon and on the surface 
of the outer reef flats. The steep slopes of these two lagoons, of different 
geological structure, being in no way due to the thin veneer of coral 
patches growing upon their respective flats and slopes, but to the fact 
that they are a continuation of the slopes of the islands once covering 
the areas of Komo and of Oneata Islands, which have been elevated 
and since their elevation have disappeared in great part, and have been 
denuded and eroded to form the platform surrounding the islands now 
remaining to attest their former greater extent. The denudation and 
erosion of these islands, being accompanied by the scouring out of the 
lagoons from the submarine platform through the action of the sea, 
caused by the incessant pouring into the lagoon of a mass of water 
which can only find its way out through the entrances into the lagoon 
or over the reef flats, where it passes out with considerable velocity, 
a velocity obtained in part from the hydraulic head, and in great part 
also from the drift due to the constant driving of the trade winds in a 
westerly direction. 

North of the Exploring Isles there are some small banks, in from 
eight to twelve fathoms least water. They are Alacrity, Jeffreys, and 
Lewis Banks. Reid Reef (Plate 20, 20°, Figs. 1-4) is a narrow encir- 
cling reef, enclosing a large lagoon with three islets, rising respectively 
toa height of sixty, ten, and twenty feet, probably of elevated limestone. 
The outer reef flat is narrow on the western side, bordered by a belt of 
heads along the inner edge. There are two passages into the lagoon on 
the western face. The length of the lagoon is about eight miles, and its 
width five. The greatest depth is twenty fathoms. 


Mbukata tanoa or Argo Reefs. 
Plates 20, 20°, Figs. 5-8, and Plate 21. 


These reefs are irregularly triangular, about twenty miles in greatest 
length. A narrow continuous outer reef flat extends along the eastern 


- a 
“8 
» 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 125 


and southern faces, but the western and northern faces are bordered by 
disconnected reef patches (Plate 21), and towards the northeastern face 
from the central part in from twenty fathoms the lagoon slopes gradu- 
ally to the 100 fathom line. The western part of the lagoon is full of 
separate patches and clusters of rocks and coral patches. Off the west 
face lie two small banks, one of which is awash, the other with two 
fathoms of least water and covered with heads. Off the east face are 
three similar small banks, all of which probably represent the remnants 
of isolated peaks or spurs of the former land covering the Argo Lagoon. 
The Argo Reef is separated from the Vanua Masi (Plates 21, 22) atoll 
by a narrow channel with a depth of 115 fathoms. 

The island of Vanua Masi is not quite half a mile long, eighty feet 
high, and is composed of elevated coralliferous limestone. Bacon Islet, 
sixty feet in height, is stated to be of volcanic origin; it lies on the 
eastern face of the narrow outer reef flat facing the lagoon. This is 
open on the southwest, where the lagoon is studded with heads and coral 
patches. The greatest depth of the lagoon of Vanua Masi is twenty 
fathoms, the average from twelve to sixteen. The southern part of the 
lagoon of Argo Reef has a depth of thirty-four fathoms, and an average 
depth of from twenty to thirty. 

We may look upon the Argo Reef (including Vanua Masi) as vastly 
more denuded and eroded than that of Vanua Mbalavu, which it re- 
sembles in many respects. The islands which probably once covered 
the whole area of the Argo Reefs have been disintegrated, and there 
remain of them only the islets in Vanua Masi and the innumerable 
heads and patches which stud the slope of the Argo Reefs. The slope 
of the Argo Reefs corresponds to that of Vanua Mbalavu, and represents 
the slope of the volcanic island which thrust up the elevated limestones 
now eroded which once covered the great part of the Argo Reef Lagoon 
as at Vanua Mbalavu. The great open stretch on the northern face of 
the Argo Reefs represents a tongue of the ocean which encroached upon 
the northern slope of the land and has left in the shallower parts only 


- heads and patches of corals, while in the deeper parts corals have not 


obtained a footing. 


Thikombia. 
Plate 17. 
We did not visit Thikombia, the northernmost island of the group, 
which I am informed is composed in part of elevated coralliferous lime- 
stone rising to a height of four hundred feet. The island is a narrow 


126 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


undulating elongated ridge with conspicuous summits (volcanic ?), one of 
which is over six hundred feet high; it is a little over six miles in 
length, and situated at the northwestern extremity of an elongated 
plateau extending fifteen miles in a southeasterly direction, with an ay- 
erage depth of thirty to over forty fathoms. The western extremity of 
Thikombia, as well as the southern half of the island, is bordered by a 
fringing reef, which extends in a long spit made up of patches and 
detached rocks for two and a half miles in a southeasterly direction. 
Gardiner states that parts of Thikombia are terraced. 


Ono i lau. 
Plate 17°, Figs. 13-16, and Plate 23°, Figs. 1-4. 


We did not visit the islands to the south of Ongea. Among them 
are the Ono i lau Islands (Plate 1), of which some are volcanic and 
others composed of elevated coralliferous limestone, the highest island 
being 370 feet high. ‘These islands are surrounded by an outer reef 
flat, elliptical in outline, about seven miles by four, which is dotted 
with islets, rocks, and coral patches. To the south of these islands are 
the small islands of Tuvana i tholo and Tuvana i ra (Plate 17%, Fig. 
13, and Plate 23%, Fig. 27), situated on the northern edges of the 
circular barrier reef which surrounds them. To the southwest of the 
Ono cluster lies Vuata Ono (Plate 17%, Fig. 14, and Plate 23*,Fig. 3), 
an oblong reef nearly three miles long and always awash. Turtle 
Island to the northeast of Ono is a narrow ridge of elevated limestone, 
rising to over two hundred feet, with a barrier reef about four miles 
long off the west face, enclosing a narrow lagoon with six fathoms of 
water and passing into a barrier reef on the east face. Vuata Vatoa 
(Plate 23°, Fig. 4) is a detached reef somewhat over two miles in its 
greatest length, enclosing a tidal basin into which there is a boat passage 
through the reef. This reef lies about two miles to the south of Vatoa, 
with two hundred and forty-six fathoms in mid‘channel. Vatoa and 
Vuata Vatoa are probably the summits of a short ridge. The presence 
of elevated coralliferous limestone in this part of Fiji shows that the 
area of elevation of the group extended to the southernmost islands. 


Viti Levu and Vanua Levu. 
Plates 3, 3°, 4, 18. 


Although there are large stretches of the shores of Viti Levu and of 
Vanua Levu (Plates 3, 3°, 4) which I have not examined, we may per- 


= NS ES 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 127 


haps assume from the information I have gathered and from an exami- 
nation of the charts, that neither they nor the smaller islands and reefs 
in the Lau Archipelago, which have been passed by, present any features 
which are likely to throw much additional light on the results obtained 
from the examination made by the “ Yaralla.” The area between the 
Yasawa group and the north shore of Viti Levu (Plate 3) has not been 
systematically surveyed. All we know is that it is full of coral patches, 
undoubtedly the eastern extension of the patches to the northwest of 
Nandi waters towards the Yasawa group. How far west of Charybdis 
Reef the extension of the deep water bay north of Vatu i ra Channel 
reaches is not known. Its northern and eastern limits off Vanua Levu 
are well defined on the charts (Plate 3). It is interesting to note that 
a very steep slope — fully as steep as any of the sea faces off the reefs or 
smaller islands of Fiji, or as steep as the sea faces of the great barrier 
reef off the south coast of Viti Leva —runs off the west side of Vanua 
Levu from the Makongai Channel beyond Yendua Island (Plate 3), and 
off the east side of Viti Levu from the horn of the reef north of Ovalau 
to opposite Charybdis Reef. Yet on this steep face the corals form 
only scattered patches over the surface of the flats, extending between 
the shore lines toward the 100 fathom line, — patches and stretches 
which are separated by wide areas in which the bottom is full of heads 
of rocks similar to those of the adjoining shores. 

Charybdis Reef and the extensive reef on the southwest side of Vatu 
ira Channel (Vatu i ra Reef), represent probably the eroded summits of 
a more or less circular island and of an elongated ridge, on the outer 
edges of which coral patches have found a footing, and of which Vatu i ra 
Islet (one hundred feet high) is the only remnant. The lagoon varies in 
depth from twenty-two to twenty-seven fathoms, “ with several passages 
into it through which the tide runs strongly.” Charybdis Lagoon is 
full of rocks and patches its average depth is about twenty fathoms ; 
its western edge is open, with rocks scattered along its face. 

An extensive fringing reef skirts the north shore of Viti Levu, which 
disappears within reach of the influence of Ba River. There is a 
wide navigable channel between it and the broad outer barrier reef 
patches, which resemble those off the east coast of Viti Levu, south of 
Moturiki Channel. 

I have not examined the shores of Vanua Levu, but according to 
Horne’ and from some verbal information relating to the barrier 


1 John Horne, “ A Year in Fiji,’ London, 1881, pp. 167, 168. Horne says that 
on the southwest side of Rambe a reef has been elevated twenty feet, and that the 


128 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


reef, its character is similar to that of Viti Levu, the substratum of 
the reef flats being either hard volcanic rocks, or stratified volcanic 
mud, or remnants of elevated limestone. The northern shore of Vanua 
Levu from Cape Undu (Plate 4) west is flanked by wide extensive 
stretches of barrier reef patches ; between them and the shore exists a 
broad navigable channel full of islands and islets, and the whole of the 
shore is also indented by deep bays separated by prominent promontories 
almost isolated from the larger island ; plainly indicating that the flats 
and patches occupy areas formerly covered by large islands or by former 
slopes of spurs from Vanua Levu itself, which have been eroded and de- 
nuded and separated from the larger island. The outer flats and patches 
of the barrier reef, which as it extends westward beyond the Mali Pas- 
sage forms the Great Sea Reef, and is nearly thirty miles distant off the 
western point of Vanua Levu. The islands and islets off the north coast 
of Vanua Levu form a broad belt of islands separated by islets, rocks, 
aud patches ; on the western extremity of the belt is Yendua Island and 
the islets extending westward. 

The existence of fringing reefs inside of barrier reefs is a very strik- 
ing feature of the Fiji coral islands. Their absence in some localities 
has been explained by Dana? on the supposition that the conditions 
are more favorable to the growth of corals on a barrier than on an 
interior fringing reef. Yet in some of the wide lagoons of Fiji the 
corals of the fringing reef grow quite as luxuriantly and to the same 
depth as those on the outer edge of the barrier reef, and are often 
more abundant than those of the lagoon slope of the barrier reef. 
Depths of five to six or seven fathoms are those of the most vigorous 
growth of corals on the outer face of such barrier reefs or encircling reefs 
as I have examined in Fiji, a depth corresponding to that observed in 
the Bahamas in similar positions. 

Some of the reefs on the northwestern face of Vanua Levu (Plate 4) 
apparently illustrate admirably the formation by denudation and erosion 
of small reef flats awash, and of reef flats destitute of islands or with 
islands encircling a shallow lagoon. It will be noticed that these flats 
and pseudo atolls rise from a comparatively shallow platform, — nine to 
twenty fathoms, — and evidently represent the different stuges of denu- 
dation and of erosion of islands which have been left on one side of the 
reef flat, or have disappeared, leaving an irregular enclosing reef, or have 


beach along Savu Savu, as well as Waikava and the adjacent islands, consists of 
coral upheaved to a height of thirty feet. 
1 Corals and Coral Islands, pp. 138, 278. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 129 


merely been denuded so as to be just awash; the scouring of the sea on 
the diminutive platform of submarine erosion having formed a shallow 
lagoon in the first instances mentioned, or a series of disconnected pools. 
These flats and atolls are in every way identical with similar reef flats or 
atolls formed from peaks or islands rising from great depths; Na Ndongu, 
Nuku i ra, Thakau Moi, Laukoto, and Thakau Levu Reefs (Plates 3, 4, 
23°, Figs. 8-19). See the similar structures of Thakau Nalolo, Thakau 
Utulei, and Nuku i ra, on the eastern part of the north shore of Vanua 
Levu (Plate 4, Figs. 8-12). 

From the eastern point of Savu Savu Bay and the western point of 
Vanua Levu the island is bordered by a fringing reef (Plates 3*, 14). 
Savu Savu Bay is protected by an extensive fringing reef off Savu Savu 
Point on the east, and by a series of wide barrier reef patches lying off 
Kumbalau Point on the west, and stretching in smaller disconnected 
patches across the southern face of the opening of the bay. To the west 
of Kumbalau Point runs an extensive plateau, the outer edge of which 
is from ten to twenty miles off shore, and varying in depth up to about 
thirty fathoms. On the outer edge of the plateau are narrow discon- 
nected patches of corals and islets and rocks (Plates 3*, 4). The plateau 
makes out in two prominent points, one, Namena Reef, elliptical in 
shape, about twelve miles long and three miles wide, to the south of 
Kumbalau Point. The reef patches enclose an irregular lagoon, in the 
southern horn of which lies the island of Namena, about 320 feet in 
height (Plate 3*). The other spit of the plateau is triangular in shape, 
and extends towards Makongai, from which it is separated by a channel 
140 fathoms in depth. The western face of the plateau is bordered 
by a line of rocks and narrow coral patches, often widely separated, 
and extending in an undulating line. 

The outline of the plateau as it forms the eastern side of Vatu i ra 
Channel is rounded, forming a deep bight off Solevu Point, and extending 
in a northeasterly direction towards Yendua Island. North of Passage 
Island (Plate 3), 104 feet high, the coral patches lose their character of 
barrier reef flats; they become small, and are often very widely separated. 
The edge of the plateau is bordered with rocks, and the slope as we go 
north becomes less steep, passing off Solevu Point gradually into the 
deeper waters north of Vatu i ra Channel. But south of Nai Thombo 
thombo Point there are extensive reef flats, probably formed upon eroded 
flats of such detached spits as Lecupi Point on the south of Mbua Bay, 
and Lamut Islet north of Solevu Point. The principal one of these reef 


flats is Thakau Levu, on which some rocks are still awash at high water. 
VOL, XXXIIL. 9 


130 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


It is very probable that this plateau off the southwest coast of Vanua 
Levu represents the denuded and eroded slope of its western coast when 
it once extended ‘near to the 100 fathom line. The only remnants of 
this former extension are the islands of Namena, Passage Island, and 
the numberless rocks and coral patches studded over the surface of the 
plateau and found along its edge. 

The reefs of Makongai and Wakaya represent a stage of denudation 
and erosion less advanced than that of the Namena Reef, and of the reefs 
extending towards Vatu i ra Channel north of Makongai Channel. 

From Cape Undu south the shores of Vanua Levu on both sides of 
Nateva Bay (Plate 4) are bordered by a fringing reef. From Savu Savu 
Bay the south shore is also protected by a fringing reef, which extends 
as far as Fawn Harbor; from there the fringing reef becomes a narrow 
barrier reef at a short distance from the shore, passing round Vienne Bay, 
and forming the Kioa Reefs, and the Florida and Texas reefs on the outer 
edge of the plateau upon which are the islands of Kioa and Rambe (Plates 
4,18). The horn of the Texas reef extends about five miles beyond 
Rambe, and returns to form a fringing and barrier reef on the north 
shore of that island, and connects with the barrier reefs off Kumbalau 
Point. 

The Rambe Plateau (Plates 4,18), as we may call the eroded eastern 
extension of Navukau Promontory, is another admirable example of the — 
mode of formation by submarine erosion of such plateaus as those off the 
southwest coast of Vanua Levu, off the eastern point of Kandavu, and 
off the east face of Taviuni. The island of Rambe rises to a height of 
over 1,500 feet ; it is nearly nine miles long, and about four and a half 
broad (Plate 18). Like Kioa, the other large island on the plateau, 
which is over 900 feet high, it is of volcanic structure. The plateau 
upon which these islands rise, and the accompanying islets, rocks, and 
patches, has a greatest depth of thirty-five fathoms, and an average 
depth of about twenty. 

The Rambe plateau and the one to the east of Taviuni (Plates 4,18), 
from which rise Ngamia and Lauthala, show more plainly than either 
Makongai or Wakaya the former connection with the larger islands of 
Vanua Levu and Taviuni. The promontory of which Cape Undu is.the 
termination would, if denuded and eroded, have resulted in the formation 
of a plateau spit similar in all respects to that constituting the Namena 
barrier reef off the south coast of Vanua Levu. And finally the further 
disintegration of such irregularly shaped islands with encircling reefs as 
those of Makongai and Wakaya (Plate 15) would give us a ready ex- 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 131 


planation of the formation of such remarkably shaped reefs as the Nanuku 
and Nukusemanu Reefs (Plate 18), from the denudation and erosion of 
an extended ridge or line of the summits of independent islands, elevated 
at the time when the great masses of ancient limestones were raised to 
various heights perhaps up to one thousand feet. 

The Great Sea Reef (Plate 1) appears on the chart as the continuation 
of the chain of which the Yasawa group of islands are the only rem- 
nants, and it may be that it represents its eastern continuation after its 
denudation and erosion, and transformation into a submarine platform 
for the growth of corals. Similarly the reefs extending to the east of 
Vanua Levu towards the Yasawa group may be the western extension of 
a range of which Sesaleka Peak and Yendua Islands formed prominent 
points. 


GENERAL SKETCH OF THE FIJI ISLANDS AND CORAL REEFS. 


I went to the Fijis under the impression that I was to visit a charac- 
teristic area of subsidence ; for according to Dana and Darwin there is 
no coral reef region in which it is a simpler matter to follow the various 
steps of the subsidence which has taken place. Dana, in his last dis- 
cussion ? of the coral reef question, states that it is impossible to find a 
better series of islands than the Fijis to illustrate the gradual changes 
(brought about by subsidence) which take place in transforming a yol- 
canic island with a fringing reef to one with a barrier reef, or to one with 
an encircling reef ring, and finally to one in which the interior island 
has disappeared and has left only a more or less circular reef ring. For 
these reasons one of the Fiji atolls promised to be an admirable location 
for boring and settling the question of the thickness of the coral reef of 
an atoll. 

My surprise was great, therefore, to find within a mile from Suva an 
elevated reef about 50 feet thick, and 120 feet above the level of the sea, 
the base being underlaid by what is locally called ‘ soapstone,” *? a kind 
of volcanic mud. The western extension of this reef can be traced at 


1 Am. Journ. of Science, Vol. XXX., August and September, 1885. Dana says: 
“The large Feejee group bears abundant evidence of subsidence in its very broad 
reef grounds, barrier islands, and atolls.” 

2 The “soapstone” is largely composed of volcanic débris, mixed with tests of 
Foraminifera, Pteropods, and Mollusks. Brady (Q. J. Geol. Soc. London, 1888, Vol. 
XLIV. p. 1) considers the Rhizopod fauna such as one would expect from a depth 
of 150 to 200 fathoms. 


132 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


points along the north side of the harbor of Suva (Plate 7), the islands 
of Lambeko, Vuo, and Dra-ni mbotu, which are respectively sixty to 
seventy feet in height, being parts of an elevated reef extending to 
low water mark, and now planed off. It was this elevated reef or its 
extension westward which we traced from the Singatoka River to the 
Nandi Waters (Plate 6). A short distance inland from the mouth 
of the Singatoka there is a bluff of about 250 feet in height, com- 
posed of coralliferous limestone. This bluff is the inner extension of the 
elevated patches and limestone bluffs visible on the shore of Viti Levu. 
I am informed by Dr. Corney that the islands of Viwa and Asawa i lau 
(Plate 3), to the northward of the Nandi Waters, are also remnants 
of this elevated limestone. 

But the traces of extensive elevation are not limited to the island 
of Viti Levu. I found that the islands on the rim of the atoll of Ngele 
Levu (Plate 17) consisted entirely of coralliferous limestone rock, 
elevated to a height of over sixty feet on the larger island. The 
northern sides of the smaller islands Taulalia and Tai ni mbeka, as 
well as the north shore of Ngele Levu, were on the outer edge of the 
rim of the lagoon, deep water running up to the shore line. We next 
found that at Vanua Mbalavu (Plate 19) the northern line of islands 
were parts of an elevated reef, forming vertical bluffs of coralliferous 
limestone rock which had been raised by the central volcanic mass of 
the main island to a height of 510 feet at Ngillangillah, at Avea to 600 
feet, at the Sovu Islands to 230 feet, and on the main island to a height 
of nearly 600 feet, while on the south of the main island the coralliferous 
limestone bluffs are very much lower, and those of Malatta and of Susui 
reach a height of 420 to 430 feet. Going farther west and south we find 
at Mango vertical bluffs of an elevated coralliferous limestone of over 600 
feet underlaid by volcanic rocks at the sea level. At Tuvutha the lime- 
stone bluffs are probably nearly 800 feet high. At Naiau they are more 
than 500 feet. At Lakemba (Plate 21) they reach a height of about 
250 feet on the southwest side of the island, the greater part of the rest 
of the island being of volcanic origin. On the island of Aiwa (Plate 21) 
the elevated limestone is fully 200 feet thick. In the Oneata group the 
highest point of the elevated bluffs is about 160 feet (Plate 21). South 
of the volcanic island of Mothe and enclosed within the same barrier 
on the island of Karoni (Plate 22), the reef is about 120 feet thick. 

On the three islands of the Yangasé group (Plate 22) the elevated 
limestone attains a thickness of 240, 300, and 390 feet, and on On- 
gea, the most southeasterly cluster we visited, it attains a thickness 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS, 133 


of nearly 300 feet. At Fulanga (Plate 22) the elevated limestone 
attains a thickness of 360 feet, at Kambara (Plate 22) it is about 
200 feet thick, and at Wangava (Plate 22) it is perhaps over 300 
feet ; these islands may be in part voleanic. Finally, at Vatu Leile, the 
most westerly island we examined, the elevated reef forming the island 
is fully 110 feet thick. 

All this plainly shows that the western and southern part of Viti Levu, 
as far south as Vatu Leile, and the whole length of the windward islands 
of the Fiji group, from Ngele Levu on the north to Ongea on the south 
(Plate 2), have been subject to an elevation of at least 800 feet ; and there 
is abundant proof that the greater part of the thickness of the elevated 
coralliferous limestone has been eroded so as to reduce it in certain 
localities to the level of the sea, or in others to leave the bluffs and 
islands and islets of limestone which we have traced at so many points. 

Unfortunately there are as yet but few soundings among the islands 
of Fiji (Plate 2). There is a line extending from Nanuku Passage 
to the Kandavu Passage, and a number of soundings to the north of 
Wailangilala and towards Thikombia, which have developed the ex- 
istence of an extensive plateau with a depth of between 300 and 400 
fathoms, from which rise all the islands forming the northeastern ex- 
tremity of Fiji (Plate 2). The soundings between Ngau and Viti Levu 
(Plate 2) also indicate shallower water to the west of that island than 
is found either east or south of it. The deep water extends northwesterly 
in the passage, parallel with Kandavu. Deep water (1,200-1,700 fathoms) 
is found in the triangle formed by Moala, Totoya, and Matuku (Plates 
2,16), showing the steep slope of Moala, from 1,200 fathoms at a distance 
of six miles, and of Matuku of 1,400 fathoms at a distance of five miles. 

The deep channel passing through the centre of the Koro Sea (Plate 
2) gradually deepens towards the south until it attains a maximum 
depth of over 1,400 fathoms east of Nairai and Ngau, becoming shallower 
towards Viti Levu (Plate 12). The water gradually deepens also in 
the Kandavu Passage from over 1.100 fathoms north of North Astrolabe 
Reef to over 1,900 fathoms southwest of Kandavu. The soundings to 
the north of Naitamba indicate a ridge with somewhat over 500 fathoms 
in depth connecting the plateaus on the two sides of Nanuku Passage 
(Plates 2,18). There are no soundings showing the depths between 
the larger clusters composing the Lau or eastern group of Fiji. It 
would add greatly to our knowledge of the connection of these groups to 
have lines of soundings connecting the different island clusters of Lau. 

All the evidence to be gathered in Fiji tends to prove that preceding 


¥34 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


the present epoch there was an extensive elevation, which lifted the 
great masses of coralliferous limestone resting upon the flanks of the 
islands to a considerable height, in some cases as high as 1,000 feet. 
The base of the limestone masses rests upon volcanic rocks, as can be 
seen at Suva, at Kambara (Plate 78), at Mango, at Lakemba, at Nai- 
tamba, and at Vanua Mbalavu (Plate 72) it shows the thickness of the 
elevated reefs to have been over 800 feet. During this period of uplift 
the physiognomy of the islands of the group must have been greatly 
changed, and still further modified by the denudation and erosion which 
have taken place since the elevation of the ancient limestones. It is to 
the changes brought about by the elevation and the subsequent erosion 
and denudation that we must look for the causes which have fashioned 
the steep slopes of the islands and reefs, and not to the growth of the 
thin crust of corals which thrive upon the reef flats forming the sub- 
stratum of the modern reef,—a substratum which in Fiji may be of 
volcanic origin or composed of elevated limestone, the sea face of which 
is the extension of the former land mass and follows its ancient slope, 
being only slightly modified by the growth of the crust of recent corals 
found upon it. 

Similar elevated reefs (probably composed of the same tertiary lime- 
stone as those of Fiji) have been described by Clark? at the Loyalty 
Islands, and also by Chambeyron (L.),? and’ Pelatan (L.).2 Chambey- 
ron gives figures of the elevated terraces of Lifou and Ouvea composed 
of coralliferous limestone, and there is an excellent photograph taken by 
Pelatan of the elevated coral reefs of Lifou, and reproduced in Bernard’s* 
Nouvelle Calédonie, p. 45. While Maré is said by Pelatan to have five 
terraces of elevated coralliferous limestone, and to be riddled with cav- 
erns,® Clark considers the elevated coralliferous limestones of the Loyalty 
Islands probably to be Pleistocene. 

In the Solomon Islands, Guppy ® has traced extensive elevated reefs, 

1 Q. J. Geol. Soc. London, 1847, Vol. III. p. 61. 

2 Bull. Soc. Géogr., 1875, p. 566, and Bull. Soc. Géogr., 1876, p. 634. 

® Les Mines de la Nouvelle Calédonie. 

4 L’Archipel de la Nouvelle Calédonie, par Augustin Bernard. Paris, 1895. 

5 See also De Rochas, La Nouvelle Calédonie, p. 90. Grundman, Die Loyalty 
Inseln, Peterm. Mittheil., 1870, p. 365. 

6 Guppy, The Solomon Islands, 1887, p. 126, and Scott, Geog. Mag., 1888, 
p. 121, a criticism of the theory of subsidence as affecting coral reefs. Geol. of the 
New Hebrides, Friedrick, Q. J. Geol. Soc. London, 1893, XLIX. 227. Campbell, R., 
Geol. Soc. of Australasia, Melbourne, 1889, VI. 19. Strehl, Zeit. f. Wiss. Geog. 
Ergiinz., No. 3, 1890. J. Walther, Bau d. Flexuren, Jena Zeits. f. Nat., 1886, p. 243. 
J. Garnier, Ann. d. Mines, 1867, p. 59. Walther, Adamsbriicke, Peterm. Ergiinz., 
No. 102. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. £35 


‘ 


which however he considers as belonging to the present epoch. Elevated 
coralliferous limestones also exist in the New Hebrides as well as on the 
southern shore of New Guinea. 

The time of this Fijian elevation we cannot at present ascertain. It is 
not unnatural to assume that it was coincident with the elevation of 
Northern Queensland, and that the area of elevation included New 
Guinea, the islands to the east of it as far south as New Caledonia, and 
as far east as the most distant of the Paumcotus (Gambier Islands), 
and extended northward of that line to include the Gilbert, Ellice, 
Marshall, and Caroline Islands; and that since this epoch of elevation 
the islands within that area have been, like Northern Australia, subject 
to an extensive denudation and erosion, many of them being reduced to 


-mere flats but a few feet above the surface of the sea, others worn away 


to represent to-day but a small portion of their former extent. It is 
upon the reef flats thus eroded, or around the islands and islets which 
are the remnants of a former period, that the corals of to-day have ob- 
tained a foothold. And further, by the mechanical action of the sea 
combined with that of the trade winds, channels have been excavated out 
of the substratum underlying the coral reefs to form the lagoons of the 
barrier reefs and atolls of Fiji. 

So that, as far as we can judge from the case of the Fiji Islands, the 
shape of the atolls and of the barrier reefs is due to causes which have 
acted during a period preceding our own. The islands of the whole 
group have been elevated, and since their elevation have, like the 
northern part of Queensland, remained nearly stationary, and exposed 
to a great and prolonged process of denudation and of aerial and sub- 
marine erosion, which has reduced them to their present height. The 
submarine platforms upon which the barrier reefs have grown being 
merely the flats left by the denudation and erosion of the central island, 
while the atolls are similar flats from the surface of which the islands 
have at first disappeared and the interior parts of which have next been 
removed by the incessant scouring of the action of the sea, the ceaseless 
rollers pouring a huge mass of water into the lagoon, which finds its 
way out of the passages leading into it or over the low outer edges of 
the jagoon. These atolls and islands, surrounded in part or wholly by 
encircling and barrier reefs, have not been built (as is claimed by Dana 
and Darwin) by the subsidence of the islands they enclose. They are 
not situated in an area of subsidence, but on the contrary in an area of 
elevation. The theory of Darwin and Dana is therefore not applicable 
to the Fiji Islands. 


136 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


The evidence of elevation is not limited to that furnished by the re- 
mains of the elevated coralliferous limestone just mentioned, and it is 
natural to assume that the elevation we have just traced was but a 
part of a more general elevation, which perhaps took place in late tertiary 
times, and in which the whole group was involved. It is plain that there 
must have been most extensive denudation and submarine erosion going on 
throughout the group for a very considerable time, geologically speaking. 
The outlines of the islands, deeply furrowed by gorges and valleys, the 
sharp or serrated ridges separating the valleys, the fantastic outlines of 
the peaks and chains of Viti Levu, Vanua Levu, and Ovalau, all attest to 
the great work of atmospheric agency which must have been going on 
for so long a period. 

The extent of the separation of the islands, islets, or isolated rocks 
from the points or spurs of the larger islands also bears witness to the 
great length of time during which submarine erosion and denudation 
have been at work. 

The platforms of submarine erosion constitute the characteristic fea- 
tures of the islauds of Fiji. A glance at the sketch map of Fiji (Plate 1) 
and at the detailed charts of different portions of the group cannot fail 
to show how extensive this action has been. I need only call special 
attention to the northwestern extremity of Viti Levu, the eastern face of 
the same island (Plates 3, 7), the southern coast of Viti Levu (Plate 5), 
the southwestern and northeastern shores of Vanua Levu (Plates 3, 4, 
18), the extensive platform of Kandavu (Plate 11), that of the northern 
extremity of Taviuni, Budd Reef (Plates 4, 18), Thikombia (Plate 11), 
the platforms of submarine erosion of Mbengha (Plate 8), of Nairai, 
Ngau (Plates 12, 13, 14), of Makongai and Wakaya (Plate 15), of 
Moala and Totoya (Plates 16, 23), of the Exploring Isles (Plate 19), and 
of the smaller islands like Kimbombo and Kanathea (Plate 19), Lakemba 
and Oneata (Plate 21), Mothe, Komo, Yangas4, and Ongea (Plate 22), 
and a host of other smaller platforms. Finally, platforms of submarine 
erosion which have reached the stage of atolls of greater size, like the 
Argo Reefs (Plate 21), Reid (Plate 20) and Nanuku Reefs (Plate 18), 
Ngele Levu (Plate 17), or those-of smaller dimensions, like Adolphus 
Reef (Plate 18), Thakau Mata Thuthu, Thakau Vutho Vutho (Plate 
17), Duff (Plate 18), Dibble’s Reef (Plate 19), Motua Levu, Motua lai 
lai (Plate 18), Thakau Tambu (Plate 20), Thakau Lekaleka (Plate 21), 
Thakau Motu (Plate 22), Thakau Levu (Plate 22), and others. 

Add to this the fact that we are in a region of a former powerful and 
extensive volcanic activity, the traces of which can still be seen in all 


‘> iP, 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 137 


directions, and which has undoubtedly played a great part in the lifting 
of the island masses and their subsequent shaping to their present out- 
lines. From this evidence I am inclined to think that the corals of to- 
day have actually played no part in the shaping of the circular or irregular 
atolls scattered among the Fiji Islands, that they have had nothing to do 
in our time with the building up of the substructure of the barrier reefs 
encircling either wholly or in part some of the islands, that their modi- 
fying influence has been entirely limited in the present epoch to the 
formation of fringing reefs, and that the recent corals living upon the 
outer margin of the reefs, either of the atolls or of the barriers, form only 
a crust of very moderate thickness upon the underlying base. This base 
may be either the edge of a submarine flat, or of an eroded elevated 
limestone, or of a similar substructure composed of volcanic rocks, the 
nature of that base depending absolutely upon its character when ele- 
vated in a former period to a greater height than it now has ; denudation 
and erosion acting of course more rapidly upon the elevated coralliferous 
limestones than upon those of a volcanic character. It is therefore natu- 
ral to find that the larger islands, like Kandayu, Ovalau, and Taviuni 
(Plates 1, 3, 4,7, 10, 11), are of volcanic origin, while the islands which once 
occupied the area of the lagoons of Ngele Levu, Nanuku Reefs, Vanua 
Mbalavu, the Argo Reefs, the Oneata, Yangasé, Aiwa, Ongea, and Vatu 
Leile clusters, were composed of elevated coralliferous limestones. They 
have disappeared almost entirely, leaving only here and there a small 
island to attest to the former existence of a more extensive elevated 
limestone, once covering the whole area of what is now an atoll (Plates 
1, 17, 18, 19-21). Smaller volcanic islands, like Matuku, Moala, Ngau, 
Nairai, and Koro (Plates 1, 12, 13, 14, 16), also show the greater or 
smaller extent to which each has been eroded after its elevation, being 
least in Koro (Plate 3*) and Matuku (Plate 16), and somewhat more in 
Moala (Plate 16) and Ngau (Plate 13), and still more in Nairai (Plate 
14), while in such volcanic islands with atolls as Mbengha (Plate 8), 
Wakaya, and Makongai (Plate 15) the denudation and submarine ero- 
sion’ has been still greater, the islands covering but a comparatively 


1 Dana (p. 280) accounts for the formation of the shore platform by the action of 
the sea. We goa little further, and assign to the action of the breakers and of the 
currents in carrying loose material to sea the formation of channels between the 
outer reefs and the shore ; these become lagoons inside of barriers or encircling reefs, 
and finally scoop out the lagoons of atolls. Dana (p. 181) insists fully as strongly as 
Darwin upon the identity of origin of the encircling atoll reef and the outer reefs 
enclosing high or low islands: “The lagoons are similar in character and position 


138 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


small area of that once covered by the island originally occupying the 
. area of the lagoon; this denudation having been carried to a still greater 
extent in the Kimbombo cluster (Plate 19), in Komo (Plate 22), and 
the islands of Duff Reef (Plate 18). This process of denudation and 
submarine erosion may have gone so far as to leave no trace in an atoll of 
its volcanic or of its limestone (elevated) origin, its shape to-day being 
entirely due to mechanical action, and having nothing to do with the 
growth of the corals which have found a footing upon the flats due to 
submarine erosion and to denudation and to the action of the atmosphere 
and of the sea. 

It seems to me as if the position of an island left on the western or 
lee edge of a lagoon depended upon the original position of its highest 
point. This appears in the case of Makongai and Wakaya. The crest 
of the former was probably near the eastern edge, while the highest point 
of Wakaya was perhaps nearest the western side of the original island 
(Plate 15). Similarly the highest summit and ridge of Vatu Leile, if our 
views are correct (Plate 9), was on the western face of the original land 
mass. The highest ridge of Rambe lies on the northwestern side of the 
submarine plateau; the islands of Budd Reef indicate its highest land to 
have been on the northern part of the plateau (Plate 18). In Mbengha 
(Plate 8), on the contrary, the highest land mass is found on the east 
face of the lagoon. In the Great Astrolabe Lagoon it was in the central 
line of the plateau (Plate 10). In Ngau (Plate 13) the highest land lies 
to the east, in Nairai (Plate 14) somewhat nearer the centre, in Moala 
in the northern part of the lagoon. In Totoya (Plate 23) the highest 
part of the rim is the eastern edge. 

The northeastern part of Ngele Levu must have been the highest ex- 
tremity of the Ngele Levu land mass (Plate 17). The islet at the north- 
eastern extremity of Wailangilala (Plate 18) indicates the position of 
the highest part of that atoll. The highest land of Naitamba, Kanathea, 
Vanua Mbalavu, and Katavanga lies on the western part of the plateau 
(Plate 19), and also that of Lakemba (Plate 21). 

The highest of the land masses of Aiwa, of Oneata (Plate 21), and 
of Komo (Plate 22) was on the southern edge of these plateaus. In 
Mothe it lay near the northern extremity (Plate 22). In Namuka and 
Ongea it ran through the central parts of the group (Plate 22). In 
Fulanga the land seems to have been equally high on the northern and 


to the inner channels within barrier reefs. . . . The reefs within the lagoons cor- 
respond very exactly in mode of growth and other characters to the inner reefs 
under the lee of a barrier.” 


rer rape 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 139 


southern edges of the laud mass (Plate 22). In Yangasd the south- 
eastern and western faces were probably the highest land of the group 
(Plate 22). 

Admiral Wharton’? has suggested “‘the cutting down of volcanic 
islands by the action of the sea, and that this action has a far greater 
share in furnishing coral foundations than has been generally admitted.” 
From our experience in Fiji we may safely modify this to the cutting 
down, not only of volcanic islands, but also of other elevated islands, 
and their cutting down not only by submarine erosion but also by 
denudation and atmospheric agencies, and thus preparing the founda- 
tions upon which recent corals have established themselves. Add to 
this the elevation of banks composed of volcanic rocks or of sedimentary 
rocks up to heights at which corals or corallines can begin to grow, 
and we have in addition to their increment in height from the increase 
due to pelagic organisms and the decay of other calcareous invertebrates 
living upon their surface all the elements needed for the preparation of 
a set of foundations from very different causes. 

I have already on other occasions called attention to the powerful 
scouring effect produced upon the interior of an atoll or lagoon, or the 
channel of a barrier reef, by the mass of water poured into it from all 
sides as the huge ocean swells break over the outer rim. This mass of 
water can find no outlet against the incessant swell ; it must escape to 


- leeward through the openings in the outer reef flats, or laterally over the 


low parts of their outer edges. It will be noticed that the openings are 
usually on the west face of the atoll, the direction in which the prevail- 
ing trades drive the water of the lagoon. The water becomes charged 
with particles of lime or of other material, and we soon have all the 
elements of a modified gigantic pothole, from which the churned mate- 
rial? is carried out by the currents flowing through the entrances into 
the lagoon. It has long been known that there is a violent rush of 
water out of the lagoons, the velocity attained reaching sometimes four 
to five knots. In Fiji I have noticed these powerful currents flowing 
out of the passages leading into the lagoons of Fulanga (Plate 22), of 
Ngele Levu (Plate 17), of Wailangilala (Plate 18), of Vatu Leile (Plate 9), 
of Totoya (Plate 23), and racing along the interior channels of the great 


1 “The Foundation of Atolls,” Nature, February 25, 1897, p. 891. 

2 Material derived mainly from the mechanical disintegration of the corals or 
substratum forming the surface of the reef, and also in part from the chemical dis- 
integration due to the sea water at work to rot and dissolve the limestones of the 
Teef. 


140 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


barrier reef stretching along the south coast of Viti Levu, especially at 
Lauthala Bay, Suva (Plate 7), and the reef harbors and passages between 
Suva and Serua (Plate 5), and out of the smaller atolls like Motua lai lai, 
Thakau Leka leka, Thakau Momo, and others (Plates 12, 18, 21). 

The strength, of the currents in the channel separating the barrier 
reef and the shore has been noticed by Semper? and by Mébius? as 
bearing an important part in Mauritius. There is in the Biologisches 
Centralblatt, 1889-90, Bd. IX. p. 564, a short review of the third edi- 
tion of Darwin’s “Coral Reefs,” showing the principal points in the 
discussion of the reefs to which Bonney has called attention. But this 
discussion is mainly theoretical, and adds no new factors in the problem. 
I would refer to what Gardiner *® says regarding the conditions affecting 
the growth of coral reefs in Fiji, where he shows the effect of tidal 
currents in the passages of reefs and inside of reefs. Strong currents 
prevent the coral larve from fixing themselves in localities which they 
scour, while the corals will thrive off the passages where the currents 
have lost their strength. The navigators and naturalists of the U. S. 
Exploring Expedition* frequently speak of the rapid outward current 
passing through the openings of the reefs, especially during the ebbing 
tide. Dana® had noticed the great strength of the tidal currents, and 
he well explains by their action the great diversity of distribution of 
material over the bottom of a lagoon or of a barrier reef channel. 

There seems to be no question that the action of the sea can cut out the 
lagoons of barrier reefs and of atolls at the depths at which they have been 
observed in the Fijis. Although there are individual atolls which show 
depths of thirty-five to fifty fathoms and even more, these are excep- 
tional depths, which are readily explained as due to other causes than 
the scouring action of the sea. 

Admiral Wharton ° has given an excellent summary of cases showing to 
what depths the action of the sea in motion may be felt to a sufficient ex- 
tent to move material at depths of fifty to sixty fathoms. As he justly 
says, “ The effect [of the action of the waves in an otherwise deep sea 
over which strong winds are continually blowing] will be to cut down an 
island more or less rapidly, according to its constitution, toa very con- 


siderable depth below the surface, the final result being a perfectly flat 
bank.” 


1 Natiirl. Existenzbeding. d. Thiere, Bd. II. (1880), chapters 7, 8. 

2 Beitrage z. Meeres Fauna der Insel Mauritius, Berlin, 1880, p. 29. 

8 Loc. cit., p. 484. * Dana, p. 170. 

5 Loc. cit., p. 151. ® Nature, Vol. LV. p. 392. 


ae we. 


peat 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 141 


On Plate 22°I have a series of hypothetical figures to illustrate the 
changes I imagine the islands of Fiji to have undergone from the time 
of their elevation to the present day. ‘The only type which is not 
represented is that of Koro, which is however sufficiently well shown 
on Plate 19*, Fig. 8. The highest point of Koro occupies a nearly 
central position, the eastern platform of submarine denudation being 
only slightly wider than the western. Koro occupies a position inter- 
mediate between Makongai and Wakaya (Plate 22°, Figs. 2, 3), where 
in the one case the widest platform of submarine erosion is situated on 
the west side, and in the other on the eastern face of the island. 

The dotted lines surmounting the Figures of Plate 22° indicate the 
hypothetical islands as they may have appeared after their elevation to 
the highest point ; the solid lines indicate the heights of the islands as 
they are at the present day, and the lower dotted lines in Figures 7 to 12 
indicate the position of the underlying volcanic rocks which have ele- 
vated the overlying coralliferous limestones in Figures 7 to 11, while in 
Figure 12 the volcanic rocks of Vanua Mbalavu are seen to pass under 
the elevated limestones of Thikombia i lau. 

In Plate 20°, Figures 1 to 5, the dotted lines represent the position of 
the volcanic rocks underlying the recent coral reefs forming the barrier of 
the harbor of Leyuka, upon the platform of submarine erosion consisting 
of voleanic rocks, as represented by the dotted lines in those Figures. 

Figures 1 to 5 represent the hypothetical outlines of volcanic islands. 

Figure 1, that of Nairai, with a narrow barrier reef off the east coast 
and a wide platform of submarine erosion on the western face, with 
heads and patches which probably represent higher points of the 
original Nairai as indicated by the dotted lines. Figures 2 and 3 
represent modifications of a volcanic island having probably in one case 
its highest point nearest the eastern edge of the lagoon, and in the 
other nearest the western side of the lagoon (Makongai and Wakaya). 

Figure 4 represents Mbengha, in which there must have been a 
western ridge, and perhaps also a central ridge, more or less parallel 
with the two main ridges of Mbengha near the eastern edge of the 
lagoon. 

Figure 5 represents the continuation of a former great ridge northward 
from Kandavu towards the North Astrolabe Reef, which has been 
denuded and eroded into a series of islands now existing in the Great 
Astrolabe Lagoon. 

Figures 6 to 11 represent the former outlines of islands composed of 
elevated coralliferous limestone. In the case of Figure 6, Tuvana i ra, 


142 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


the central limestone hill is flanked by two nearly equal platforms of 
submarine erosion which are scarcely more than reef flats. In Figures 
8 and 10 are represented conditions in which, as in Vatu Leile, we have 
a very shallow lagoon with reef flats both on the east and west, and the 
remnant of the original island rising to a hundred feet at the western 
face. In Figure 10 we have the eastern end of the Ngele Levu Lagoon, 
with the islet of Taulalia on the north side of a shallow lagoon. Imme- 
diately beyond Taulalia all trace of the former elevated island composed - 
of limestone disappears ; the lagoon becomes deeper as we pass to the 
western entrances, and the only traces left of the original Ngele Levu 
Island are the extensive reef flats on the north and south side of the 
deeper lagoon. 

Figures 9 and 11, Ongea and Oneata, indicate the amount of erosion 
and denudation which probably has taken place to reduce the islands as 
originally elevated to their present condition. 

Figure 7 represents the manner in which the great central Sound of 
Fulanga, with its narrow outer lagoons, has probably been formed by 
the denudation and erosion of the central part of the limestones com- 
posing the island, aided by the solvent action both of the fresh water 
finding its way through the central limestone mass, and that of the salt 
sea after it had once gained access to the inner Sound of Fulanga. 

Figure 12 gives a hypothetical section across Vanua Mbalavu, show- 
ing the extension westward of the volcanic rocks which have raised the 
island of Thikombia i lau, near the central part of the lagoon, composed 
of elevated limestone. The elevated limestone to the westward of 
Thikombia either having all been denuded and eroded or broken up 
into masses readily decomposed, the fragments of which still exist to the 
northeast towards Ngillangillah and south towards Malatta Island. 

The sections which I have given (Plates 11°, 17°, 19°, 20°, 22°, 22°) 
plainly indicate the general flatness’ of the lagoons, with a slight 
inclination in the direction of the flow of the water in the lagoon 
toward the ship passages leading into the lagoon, and the outline of 
the islands which have first been cut down by atmospheric agencies 
show irregularities which disappear finally when they have come 
within the scope of submarine erosion, resulting in such ‘‘ sunken” 
banks as the Penguin Bank (Plate 23%, Figs: 7, 13). By “sunken” 
we do not mean in any way to refer to subsidence as a factor in 
producing such a bank, The mass of water which is poured into a 
lagoon on the windward face of a reef, and transforms it into a gigantic 
pothole, is something enormous. The breakers follow one another in- 


6 


—S 


-ey 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 143 


cessantly, and the hydraulic head obtained is amply sufficient to account 
for the scouring of the lagoons after the reef has once established it- 
self as a bank, and amply sufficient to wear away from the slope of 
the islands the platform upon which the coral reef is built. The to- 
pography of this platform is naturally much varied, depending upon the 
character of the shore line, the direction of the valleys of the shore 
hills, and their composition. A glance at the charts accompanying this 
Bulletin will show all possible conditions of submarine erosion in the 
cutting down of the submarine platforms of the islands of Fiji, and 
in the manner in which islands, islets, and rocks have been left, attesting 
their former greater extension in the various clusters of the Archipelago. 

When the principal openings are not on the lee side of the lagoons, as 
is the case with Vanua Mbalavu (Plate 19), and the Argo Reef or Totoya 
(Plate 23), Fulanga (Plate 22), and a few others, there is usually a sim- 
ple reason, such as the lower elevation of the island once covering the 
area of the lagoon at some point not on the lee side, or the fact that the 
lagoon has been formed on a steep volcanic slope looking eastward or 
northward, so that deep ravines or tongues of deep water cut into the 
lagoons, and intercept the coral patches forming its rim on the weather 
side, and thus leave a windward passage. It is by some such orogenic 
condition that we must explain the existence of deep soundings within 
atolls, — soundings which in no way indicate a subsidence, as has been 
assumed by Darwin, and which according to him were not to be ex- 
plained by any other hypothesis. Such deep ravines are of course also 
to be traced on the slopes of the larger islands where we fiud, crossing the 
shallow plateaus on which coral patches grow, valleys of considerable 
depth, which appear as deep soundings within the area of an outer reef 
flat such as in the great plateau off Viti Levu and Vanua Levu (Plates 
3*, 4), or of Kandavu (Plates 10, 11) and Taviuni (Plate 4), which 
according to Darwin would indicate a subsidence, while, on the con- 
trary, they are a part of the results of the elevation and lifting up of 
that region of Fiji. 

Nor are the great depths found close to narrow lines of corals an 
indication that the corals have grown up as a nearly vertical wall from a 
depth of two to three hundred fathoms or more. It merely indicates 
that the corals form a thin crust, at most 120 feet in thickness, over a 
sharp volcanic ridge, the summits or crest of which have either reached 
by elevation the depths at which corals can grow, or have been denuded 
by submarine erosion to form a platform below the level of the sea, 
where corals have found a footing upon them. 


144 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 


My observations in Fiji only emphasize what has been said so often, 
that there is no general theory of the formation of coral reefs, either of 
barrier reefs or atolls, applicable to all districts, and that each district 
must be examined by itself. At least such has been my experience in the 
Bermudas, the Bahamas, Cuba, Florida, the West Indies, the Sandwich 
Islands, and Australia. The results of this trip show plainly that Dar- 
win’s theory is not applicable to the Fiji Islands, notwithstanding the 
borings at Funafuti, and that, in all the cases I have examined, the reefs 
form but a thin crust upon the underlying base, the shape and composi- 
tion of which is not in any way due to the growth of corals of the 
existing period. 


CAMBRIDGE, MASSACHUSETTS, 
October Ist, 1898. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 145 


Py yr eX, 


ABROLHOS ISLANDS, p. 9. 

Adolphus Reef, pp. 13, 22, 35, 66, 100, 101, 
107,186. Pls. 1,18, 22a, 

Ahii Island, p. 6. 

Aiwa Islands, pp. 13, 29, 35, 48, 53, 54, 55, 
85, 96, 132, 137, 1389. Pls. 1, 21, 22a. 

Alacran, p. 41. 

Alacrity Bank, p. 124. Pl. 18. 

Alacrity Bay, Pl. 3. 

Alacrity Pass, p. 80. Pl. 11. 

Alacrity Rocks, p. 30. Pl. 10. 

Alexa Bank, p. 101. 

Algee, List of, p. 121. 

Allardyce, W. L., pp. 3, 65. 


_ American Passage, pp. 89, 92,93. PI. 19. 


Andiwathe Island, Pl. 19. 

Andiwathe Passage, p. 89. 

Andrews, E. C., p. 82. 

Aratica Island, p. 6. 

Argo Reefs, pp. 29, 72, 121, 124, 125, 136, 
137, 143. Pls. 1, 20, 20a, 21, 22b, 

Asawa i lau, pp. 117, 182. Pl.1. 

Aso San, p. 108. 

Atiu, p. 79. 

Atolls, Sundry, pp. 99-103. 

Avea Island, pp. 89, 90, 91,1382. Pl. 19. 


Pl. 19. 


Ba River, p. 127. Pl. 3. 
Bache Fund, p. 72. 
Bacon Island, p. 125. Pl. 20. 


Bahamas, pp. 10, 41, 44, 128. 


_ Bahia, p. 9. 


Baker Island, p. 69. 


Barracouta Passage, p. 61. Pl. 22. 
Bartlett Deep, p. 76. 
Beagle Passage, p. 33. PI. 11. 


Beechey, Capt., p. 79. 
Bell Reef, pp. 13, 35, 88, 100, 107. Pls. 1, 
19. 


Bermudas, pp. 10, 40, 41, 65. 
Bernard, A., p. 184, 

Bird Island, p. 26. Pl. 8. 
Birnie Island, p. 69. 


£0) FED. O.O.9 00 O 10 


Biscayne, Key, p. 10. 
Bismarck Archipelago, p. 8. 
Blackswan Point, pp. 15, 90, 93. 
Boehm Rock, p. 96. Pl. 19. 
Bololo, pp. 16, 113. 
Bonney, Prof., pp. 7, 9, 10, 13, 79, 140. 
Booby Rock, Pl. 20. 
Bourne, pp. 9, 41. 
Breaknot Rocks, p. 42. 
Brown Passage, Pl. 17. 
Budd Reefs, pp. 29, 33, 34, 35, 36, 49, 71, 
136, 138. Pls. 1, 4, 18, 70. 


FI. 19. 


Pls. 4, 18. 


CzsaAr Rocks, Pl. 8. 

Caroline Islands, pp. 6, 108, 135. 
Challenger Mount, Pl. 10. 
Chambeyron, p. 134. 

Chamisso, p. 109. 


Champion Rocks, p. 42. Pl. 4. 
Chapeirees, pp. 4, 9. 
Charybdis Reef, p. 127. Pls. 1, 3. 


Clermont Tonnerre, p. 6. 
Clipperton Atoll, pp. 106, 107. 
Cock’s Bank, p. 122. Pl. 4. 
Cocks, Capt. R., pp. 54, 128. 
Combe Bank, PI. 21. 

Corney, Dr., pp. 117, 132. 

Craig, p. 113. 

Crosby, O. W., p. 10. 

Cuba, p. 10. 

Cutter Passage, p. 26. PI. 8. 

Daun, Dr., p. 8. 

Dall, W. H., pp. 81, 92. 

Dana, J. D., pp. 5, 6, 18, 27, 40, 47, 55, 67, 
74, 76, 78, 79, 82, 83, 102, 103, 104, 115, 
120, 128, 131, 135, 138, 140. 

Darwin, C., pp. 5, 6, 8, 9, 10, 11, 12, 13, 35, 
40, 41, 47, 67, 71, 73, 74, 75, 78, 82, 102, 
103, 115, 131, 135, 138, 140, 143, 144. 

David, pp. 47, 72, 82. 

Davidson, Prof., p. 106. 

Davura, Pl. 23a, 


146 


Dean Island, p. 6. 
Deep Bay, p. 20. 
Deep Passage, P]. 17. 
Dibble’s Reef, pp. 35, 88, 122, 186,138. Pls. 
= itl Dei I? 
Dra ni mbotu, p. 132. 
Duff Reef, pp. 35, 101, 122, 136. Pls. 1,18. 
D’Urville Channel, p. 32. PJ. 10. 


ELEVATED LIMESTONE ISLANDS, p. 43. 

Elizabeth Island, p. 6. 

Ellice Islands, pp. 6, 73, 83, 109, 135. 

Enderbury Island, p. 7. 

Ethel Reefs, Pl. 3. 

Eua Island, pp. 78, 79. 

Everglades, p. 10. 

Exploring Isles, pp. 18, 29, 72, 88, 128, 124, 
36. Pls. 1, 19, 19a, 72-76, 

Extinct Craters, p. 105. 


FaAKAoru IsLAnp, p. 7. 

Fakarava, p. 6. 

Falcon Island, pp. 78, 108. 

Farlow. p. 121. 

Fawn Harbor, p. 130. 

Field, Captain, p. 101. 

Fiji Islands, Classification of, p. 17. 

Fitzroy, Capt., p. 6. 

Florida Reefs, p. 130. Pls. 4, 18. 

Forbes, p. 41. 

Foster, p. 79. 

Frech, pp. 74, 121. 

Friendly Islands, pp. 6, 7, 8. 

Frigate Passage, -pp. 26,28. Pl. 8. 

Fritsch, p. 73. 

Frost Reef, p. 123. Pl. 19. 

Fulanga Island, pp. 13, 17, 34, 53, 60, 62, 63, 
64, 65, 69, 72, 84, 85, 95, 132, 139, 142, 143. 
Pls. 1, 22, 22a, 80-84. 

Fulanga Passage, pp. 75, 84. 
22d, 

Fulanga Sound, p. 69. 

Funafuti, pp. 41, 47, 72, 78, 83, 84. 


Pls. 1, 22, 


GAMBIER ISLANDS, p. 135. 

Gangway Rocks, p. 42. Pls, 4,18. 

Gardiner, pp. 17, 18, 29, 48, 62, 65, 76, 84, 
85, 96, 99, 121, 126, 140. 

General Sketch of Fiji, p. 131. 

Georgia Channel, PI. 18, 

Gilbert Islands, pp. 6, 7, 83, 109, 135. 

Graeff, Dr., p. 8. 

Great Astrolabe Lagoon, 32. 

Great Astrolabe Reef, pp. 14, 29, 30, 31, 32, 
138. Pls. 1, 11,11, 51, 59. 

Great Barrier Reef, pp. 10, 41, 128, 130. 

Great Sea Reef, pp. 115, 131. Pls. 1, 4. 

Gregory, T. W., p. 78. 


BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Gullet Passage, pp. 37, 38, 105. Pl. 23. 
Guppy, pp. 41, 134. 


HALEAKALA, p. 107. Pl. 71. 

Hartt, C. F., p. 8. 

Hawaiian Islands, p. 6. 

Hedley, p. 84. 

Heilprin, p. 8. 

Henderson Island, p. 79. 

Herald Pass, Pl. 11. 

Herald Roadstead, p. 20. Pl. 13. 

Herald Sound, p. 20. Pl. 23. 

Hervey Group, p. 79. 

Hickson, p. 29. 

HR Le pe 1S . 

Hogsty, pp. 41, 102. 

Honden Island, p. 6. 

Honolulu, Borings at, pp. 82, 83, 87. 

Horne, pp. 18, 71, 127. 

Horseshoe Reef, pp. 14, 34, 101, 107, 123. 
Pls. 1, 3a, 14, 23a, 

Howland Island, p. 66. 

Hull Island, p. 7. 


IameEu IsLanD, Pl. 4. 

Islands from Charts, p. 121. 

Islands partly Volcanic and partly Lime- 
stone, p. 88. 


JEFFREY’S Bank, p. 124. Pl. 18. 


John Wesley Bluffs, pp. 28,29. Pl. 10, 
Jones, E. G., p. 92. 

Judd, Prof., p. 79. 

Karmbo ISLAND, pp. 53, 54. Pl. 19. 


Kambara Island, pp. 14, 48, 52, 53, 68, 75, 
79, 80, 81, 85, 98, 99, 133. Pls. 1, 22, 
22a, 77-79. 

Kanathea Island, pp. 29, 96, 98, 186, 138. 
Pilsen. 

Kandavu Island, pp. 14, 17, 18, 28, 29, 30, 
31, 32, 33, 41, 71, 117, 130, 133, 134, 136, 
137, 142, 144. Pls. 1, 10, 11, 22, 50, 

Kandavu Passage, p. 133. Pl. 1. 

Kandavu Town, PI. 10. 

Kaneohe Bay, pp. 8, 11. 

Karoni Islet, pp. 97, 98, 132. Pl. 22. 


,Katavanga Island, pp. 35, 54, 70, 123, 138. 


Pls.,1,; 19: 

Kawehe Island, p. 6. 

Kean Island, p. 69. 

Keeling Atoll, p. 6. 

Kent, W. Saville, pp. 7, 121. 

Kia Island, Pl. 4. 

Kimbombo Islets, pp. 13, 17, 35, 70, 82, 88, 
100, 123, 136, 137. Pls. 1, 19, 61. 

Kini Kini, pp. 38, 39. Pl. 22. 

Kinsilk Islands, p. 118. 


, 


en 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 


Kioa Island, pp. 42, 130. Pls. 4,18. 

Kioa Reefs, p. 130. Pl. 4. 

Kobu Island, pp. 21, 122. Pls. 12, 14, 59. 

Komo Island, pp. 13, 17, 35, 36, 37, 70, 107, 
120, 124, 130, 187,189. Pls. 1, 19, 22, 
63-65. 

Komo Lagoon, p. 13. 

Komo Nadriti Islet, p. 35. 

Konaoe Island, P]. 23. 

Koro Island, pp. 13, 17, 18, 187, 141. 
1, 3a, 19a. 

Koro Levu Islet, pp. 32, 42. Pl. 4. 

Koro Levu Town, pp. 32, 110. PI. 6. 


Pl. 22. 


EIS: 


Koro Mbasanga, pp. 90,91. PI. 19. 
Koro Sea, pp. 71, 1383. Pl. 1. 


Krimer, Dr., pp. 8, 13, 41, 73, 108, 109. 
Kumbalau Point, pp. 129,130. Pl. 4. 


LacGoons, p. 103. 

Lakemba Island, pp. 13, 17, 29, 95, 96, 98, 
107, 132, 134, 136, 138. Pls. 1,19, 20, 21. 

Lambeko, p. 132. 

Lamut Island, p. 129. 

Langenbeck, R. v., pp. 7, 73, 74. 

Laté i Tonga Islet, Pl. 20. 

Latéi Viti Islet, Pl. 20. 

Lau Group, Pl. 1. 

Laukoto Reef, p. 129. 

Lauthala Harbor, pp. 114, 140. 

Lauthala Island, pp. 42, 43, 130. 
18. 

Lauthala Reef, p. 99. 

Laveine Point, p. 42. Pls. CMs ko) 

Lecupi Point, p. 129. Pl. 4. 

Leluvia Island, p. 114. Pl. 7. 

Lendenfeld, R. v., pp. 29, 73, 76, 104, 105. 

Levuka Harbor, pp. 36, 111, 112, 113, 117, 
141. Pls. 7, 204, 22a, 

Lewis Bank, p. 124. 

Lifu, p. 134. 

Likuri Harbor, p. 116. 

Likuri Island, Pl. 6. 

Lister, J. J., pp. 8, 18, 77, 78, 79, 108. 

Loa Islet, p. 56. Pl. 2. 


Pls. 3, 238, 
Pl. 5. 
Pls. 4,5, 


Pi. 6. 


Lomaloma, pp. 91, 92. PI. 19. 
Lookout Reef, p. 88. Pl. 19. 
Maaru Rock, p. 123. Pl. 20. 


Makondranga Island, p. 24. Pl. 15. 

Makongai Island, pp. 13, 23, 24, 25, 42, 82, 
129, 130, 186, 137, 138, 141. Pls. 1, 3a, 
lla, 15. 

Makongai Passage, p. 127. 

Malacca Straits, p. 7. 

Malan Bank, PI. 20. 

Maiatta Island, pp. 88, 89, 91, 132, 142. 
Pl. 19. 


Pl. 3a, 


147 


Malatta Reefs, pp. 28, 29. Pl. 10. 
Maldives, pp. 35, 76. 


Malevuvu Reef, pp. 35, 122,123. Pls. 1,19. 


Mali Passage, p. 128; PI. 4. 
Malima Islets, p. 123. Pls. 1, 19. 


Malolo Barrier Reefs, Pls. 3, 6. 

Malolo Islands, pp. 117, 118. Pls. 3, 6. 

Malolo Passages, Pls. 3, 6. 

Malolo lai lai Island, P1. 3. 

Mamanutha Islands, Pls. 1, 3. 

Mambulitha Reef, p. 21. Pl. 12. 

Mana, pp. 117, 118. Pls. 3, 23a, 

Mango Island, pp. 13, 47, 48, 53, 60, 75, 80, 
81, 85, 93, 94, 95, 96, 119, 120, 123, 132, 
134. Pls. 1, 19, 224, 85-87. 

Manhii Island, p. 6. 

Marambo Island, pp. 17, 68. 

Maré, p. 134. 

Marshall Islands, pp. 6, 155. 

Martin, p. 18. 

Masamashu Island, p. 79. 

Matangi Island, 42. 


Pls. 1, 22. 


Matangi Passage, pp. 13, 15, 42. Pls. 4, 
18. 

Matanuku Island, p. 32. Pl. 10. 

Maté Rock, p. 42. Pls. 4, 18. 

Matuku Island, pp. 133,137. Pls. 1, 16. 


Mauritius, pp. 6, 11. 

Mayer, A. G., p. 15. 

Maysi, Cape, p. 78. 

Mbatiki, pp. 14,19. Pl. 1, 12. 

Mbau Island, pp. 14,110, 113,115,120. PI. 7. 
Mbengha Island, pp. 13, 17, 25, 26, 27, 29, 


36, 70, 107, 111, 136, 187, 138,141. Pls. 
1, 8, 114, 22>, 46-49. 
Mbengha Lagoon, pp. 26, 27. Pl. 8. 
Mbengha Passage, pp. 15, 26. Pls. 5, 8. 
Mbengha Reef. p. 28. 
Mbua Bay, p. 129. Pls. 3, 4. 
Mbuimbani, p. 42. Pl. 4. 
Mbukata tanoa Reefs, p. 124. Pl. 21. 
Mbulia Island, pp. 30, 31. Pl, 11. 
McCandless, J. A., pp. 82, 83. 
McPherson Rocks, p. 42. Pl. 18. 


Metia Island, pp. 6, 79. 

Miller Reef, Pl. 18. 

Moala Island, pp. 14, 18, 19, 20, 78, 82, 108, 
138, 186, 187. Pls. 1, 16, 57. 

Mobius, p. 140. 


Mokaluva, p. 114. Pl. 5. 


Monu Island, p. 118. Pl. 3. 
Moore, p. 52. 
Morse Reef, p. 96. PI. 19. 


Mothe Island, pp. 13, 17, 29, 97, 98, 102, 107, 
123, 182, 1386, 189. Pls. 1, 22. 

Moturiki Channel, pp, 14, 101, 127. Pls. 3, 7. 

Moturiki Island, pp. 26, 110, 111, 112, 113, 
tid. Pls. 33-7. 


148 BULLETIN: MUSEUM OF 


Motua Levu Reef, pp. 13, 34, 40, 69, 99, 101, 
107, 136. Pls. 1, 4, 18. 

Motua lai lai Reef, pp. 13, 34, 40, 69, 75, 99, 
101, 107, 136, 140. Pls. 1, 18, 112. 

Mumbualau Island, p. 114. Pl. 7. 

Mungaiwa Island, p. 34. Pl. 18. 

Munia Island, pp. 88, 90,91, 93. PI. 19. 

Murray, Sir John, pp. 30, 41, 79. 


Na LULU, pp. 112, 118. 

Na Ndongu, p. 129. Pls. 4, 23a. 

Na Potu, Mothe Island, p. 98. Pl. 22. 

Na Tandola Harbor, Pl. 6. 

Na Vatu Reef, p. 122. 

Na Vunivatu, p. 114. Pl. 37. 

Naiabo Islet, pp. 60, 128. Pl. 22. 

Naiau Island, pp. 13, 51, 52, 53, 67,.75, 85, 
122, 132. Pls. 1, 20, 22a, 

Nai Ngalo Ngalo Harbor, Pl. 10. 

Naingani, Pl. 7. 

Naingoro Pass, P]. 11. 

Nairai Island, pp. 14, 21, 22, 29, 70, 71, 82, 
101,'133, 136, 137, 141. Pls. 11a, 12, 14, 
22d, 58, 59. 

Naiselesele Point, p. 42. Pl. 18. 

Naitamba Island, pp. 14, 53, 97, 138, 134, 
138. PJ. 19. 

Nai Thombo thombo Point, p. 129. 

Namena Island Reef, pp. 41, 42,129. Pls. 
1, 3a, 

Namuka Harbor, p.115. Pl. 5. 

Namuka Island, pp. 17, 53, 116. Pl. 1. 

Namuka i lau, pp. 57, 60, 123,139. Pl. 22. 

Nandi Bay Waters, pp. 14, 116, 118, 127, 
IGP ed rs 

Nandi Plateau, p. 117. 

Nandronga Harbor, pp. 14, 116. PI. 6. 

Nangaidamu Harbor, p. 18. Pl. 3a, 

Nanggara, p. 115. 

Nanuka Island, pp. 64, 78. Pl. 5. 

Nanuku Islets, p. 49. Pls. 18, 103-107. 

Nanuku lai lai, p. 50. Pl. 107, 

Nanuku Levu, p. 50. Pls. 103-106. 

Nanuku Passage, pp. 26. 133. Pls. Le: 

Nanuku Reefs, pp. 13, 26, 49, 50, 131, 136, 
vie) bis. 1, 18. 

Nasilai, Pls. 5, 7. 

Nasilai Light, p. 114. Pl. 5. 

Nasilai Reef, Pl. 5. 

Nateva Bay, p. 130. Pls. 1, 4. 

Nathomaki Point, p.19. Pl, 3a, 

Navigator Islands, p. 6. 

Naviti Island, Pls. 1, 3, 

Navua River, p. 115. Pl. 5. 

Navuka, p. 130. PI. 4. 

Navula Passage, pp. 14,117. Pls. 3, 6. 

Navula Reef, Pls. 3, 6. 

Navutuiloma Island, pp. 58, 59,60. Pl. 22. 


COMPARATIVE ZOOLOGY. 


Navutuira, pp. 58, 59. Pl. 22. 

Ndaku Isthmus, Pl. 10. 

Ndelai, p. 113. 

Ndravuni Island, p. 31. Pl. 11. 

New Caledonia, pp. 134, 135. 

New Hebrides, p. 77. 

Ngamia Island, pp. 42, 48,71, 130. Pls.1, 4. 

Ngasi Mbali Island, p. 81. Pl. 11. 

Ngau Island, pp. 14, 17, 21, 22, 71, 82, 133, 
136, 137, 138. Pls. 11a, 12, 13. 

Ngava Passage, p. 112. PI. 7. 

Ngele Levu, pp. 13, 17, 43, 44, 47, 48, 49, 53, 
60, 64, 69, 70, 75, 79, 80, 81, 83, 84, 104, 
122, 132, 123, 136, 137, 138, 189, 142. 
Pls. 1, 17, 174, 22>, 95-99, 

Ngillangillah Island, pp. 78, 80, 88, 89, 90, 
93, 96, 120, 132, 142. Pls. 19, 22», 

Ngillangillah Passage, pp. 13, 88, 93. Pl. 
19. 


Ngoala Harbor, p. 30. Pl. 10. 

Nisithi Reefs, Pl. 8. 

Nisithi Rocks, p. 26. Pl. 8. 

Niue Island, p. 79. 

Ninara Island, p. 31. Pl. 11. 

North Astrolabe Reef, pp. 14, 28, 29, 30, 32, 
33, 70, 183, 141. Pls. 1, 11, 11a, 22», 
53, 54. 

Nuku ira Island, p. 129. Pls. 4, 23a. 

Nuku Levu, p. 54. Pl. 19. 

Nukulau Island, p. 114. Pls. 5, 38-41. 

Nuku Mbalate, p. 49. Pl. 18. 

Nuku Mbasanga Island, pp. 13, 49. Pls. 
18, 222, 108. 

Nuku Mbasanga Reef, pp. 49, 72. Pl. 18. 

Nuku Songea, pp. 62,123. Pl. 22. 

Nuku Thikombia Reef, p. 122. Pl. 19. 

Nukusemanu Island, pp. 49,50. Pl. 18. 

Nukusemanu Reef, pp. 15, 50, 131. Pl. 18. 

Nukutolu Islets, p. 128. Pl. 19. 


Oany, pp. 8, 11. 

Oatafu Island, p. 7. 

Observatory Point, p. 44. Pl. 17. 

Oldham, Commander, p. 78. 

Olorua Island, pp. 36, 37. Pls. 1, 22, 

Oneata Island, pp. 56, 60, 64, 69, 70, 72, 80, 
81, 96, 102, 132, 136, 1387, 189, 142. Pls. 
1, 21, 22, 22a, 22», 

Oneata Lagoon, p. 13. PI. 22. 

Oneata Passage, Pls. 1, 21. 

Ongea Islands, pp. 13, 17, 29, 47, 53, 58, 60, 
62, 69, 70, 72, 80, 81, 85, 124, 126, 132, 133, 
136, 137, 139, 142. Pls. 22,228, 22>, 94, 

Ongea Lagoon, p. 13. 

Ongea Levu, pp. 60, 61, 69. Pls. 1, 22. 

Ongea Ndriti, pp. 60, 61, 69. Pl. 22. 

Ono Island, pp. 14, 18, 30, 31, Pl. 11. 

Ono i lau Islands, p. 126. Pls, 1, 17a, 23a, 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 149 


Ortmann, p. 8. 

Ouvea, p. 134. 

Ovalau Island, pp. 6, 13, 18, 41, 110,111, 112, 
113, 120, 127, 136, 137. Pls. 1, 3, 3a, 7. 

Ovatoa, Pl. 233, 


PAssaGE ISLAND, pp. 129, 180. 

Paumotus, pp. 6, 79, 81, 83, 108, 135. 
Pelagic Fauna, p. 14. 

Pelatan, p. 134. 

Pelew Islands, p. 41. 

Penguin Bank, pp. 101, 148. Pls. 22b, 23a, 
Phillips Rock, p. 42. PI. 18. 

Pheenix, p. 69. 

Pitman Reef, pp. 34, 40, 99,100,107. P1.18. 
Pourtalés, L. F., p. 87. 

Pratt Reefs, p. 26. Pl. 8. 


Quorn HI1t, pp. 62, 64. Pl. 22. 


RaMBE I[sLAnD, pp. 42, 127, 130, 138. Pls. 
1, 4,18. 

Rara ni Tinka Island, p. 34. Pls. 4, 18. 

Raraka Island, p. 6. 

Rat Passage, p. 115. 

Rathbun, R., p. 8. 

Red Earth, p. 98. 

Reid Haven, pp. 53,69. Pl. 20. 

Reid Reef, pp. 70, 124, 136. Pls. 1, 20. 

Rein, p. 41. 

Renard Passage, Pl. 11. 

Rendell Passage, P1. 17. 

Rewa River, pp. 114, 115. PI. 5. 

Rewa Roads, Pl. 5. 

Ringgold Isles, pp. 13, 40,105. Pls. 1, 4,18. 

Rose Island, p. 12. 

Rothpletz, p. 29. 

Round Island, Pls. 1, 3. 

Rovondrau Bay, p. 115. Pl. 5. 

Rukua, p. 26. Pl. 8. 


Samoa, pp. 6, 8, 12, 77, 78. 

Savu Savu, pp. 128, 129, 130. Pl. 4. 

Scatterbreak Channel, Pl]. 17. 

Semper, pp. 12, 41, 140. 

Serpuline Atolls, pp. 40, 76. 

Serua Harbor, pp. 116, 140. Pl. 6. 

Serua Reef, p. 115. Pls. 5, 8. 

Sesaleka Peak, p. 131. 

Shark Reef, Pl. 5. 

Simonoff, Pl. 1. 

Singatoka River, pp. 14, 116, 117, 132. Pl. 6. 

Solevu Point, p. 129. Pl. 4. 

Solianga, p. 25. Pl. 8. 

Sollas, pp. 29, 72, 84, 86. 

Solo Rock Light, pp. 14, 30, 32, 33. Pls. 11, 
53. 


Solomon Islands, pp. 41, 77, 134. 


Somo Somo Strait, pp. 15,42. Pls.1,4, 18_ 

Sooloo Sea, p. 7. 

Soso Bay, p. 28. 

Sounds of Fiji, p. 68. Pl. 22. 

Sovi Harbor, Pl. 6. 

Sovu Islets, pp. 89, 91,132. Pl. 19. 

Sovu Passage, Pl. 19. 

Stebbing, p. 29. 

Stone Axe Roads, p. 19. Pl. 3a, 

Storm Islet, pp. 26, 27. Pl. 8. 

Stuart Islet, p. 26. Pl. 8. 

Sulphur Passage, p. 26. Pl. 8. 

Susui Island, pp. 88, 90, 91, 120. Pb 19. 

Suva, pp. 13, 14, 47, 48, 72, 80, 92, 114, 115, 
116,140. Pl. 5. 

Suva Harbor, pp. 13, 15, 116, 117, 118, 119, 
120, 1382. Pls. 5, 24-30. 

Suva Reef, p. 118. Pls. 5, 24-31, 65, 76. 

Swain’s Island, p. 7. 


TAHITI, pp. 6, 41. 

Tai ni Mbeka Islet, pp. 43, 44, 132. Pi. 17. 

Taiaro, p. 6. 

Tambaka Island, p. 24. Pl. 15. 

Taputeuea, p. 7. 

Tasman Strait, p. 42. Pls. 4, 18. 

Taulalia Islet, pp. 44, 132, 142. Pls. 17, 22». 

Tavanuku i vanua Reef, pp. 122, 123. Pl. 20 

Tavanuku i wai Reef, pp. 122, 123. Pl. 20. 

Taviuni Island, pp. 13, 17, 18, 41, 42, 71,78, 
130, 136, 187, 144. Pls. 1, 4, 18, 60. 

Tavuki Bay, p. 28. 

Tavuki Village, pp. 28, 111. Pt. 10. 

Tavukie Isthmus, Pl. 10. 

Tavunasithi Island, pp. 72,123. Pls. 1, 22. 

Texas Cape Reef, p. 130. Pk. 4, 18. 

Thakau Lasemarawa, pp. 40, 122, 123. Pls. 
1, 20. 

Thakau Lekaleka, Lau, pp. 13, 40, 69, 102, 
107, 136, 140. Pls. 1, 21,111. 

Thakau Levu, Lau, pp. 60, 69, 122, 123, 136. 
Pls. 2; 22: 

Thakau Levu, Vanua Levu, p. 129. 
4, 23a, 

Thakau Mata Thuthu, pp. 35, 69, 122, 136. 
Pls aie 

Thakau Moi, p. 129. Pls. 3, 238. 

Thakau Momo, pp. 40, 101, 102, 123, 140. 
Pls. 38, 12, 14, 23a, 

Thakau Motu, pp. 66, 122,136. Pls. 1, 22. 

Thakau Nalolo, p. 129. PI. 4. 

Thakau Nasokesoke, pp. 60, 123. Pl. 22. 

Thakau Nawa, p. 128. PI. 20. 

Thakau Ndavui, Pl. 7. 

Thakau Nokeva, p. 122. Pl. 20. 

Thakau Reivareiva, pp. 60. Pl. 22. 

Thakau Tambu, pp. 35, 69, 122, 136. Pls. 1, 
20, 


Pls. 3, 


150 BULLETIN: MUSEUM OF 

Thakau Teteika, pp. 62,120. Pl. 22. 

Thakau Thikondua, pp. 60, 123. Pl. 22. 

Thakau Utulei, p. 129. Pl. 4. 

Thakau Vau, pp. 122, 123. Pl. 22. 

Thakau Vuite, pp. 37,122. Pl. 22. 

Thakau Vutho Vutho, pp. 35, 69, 122, 136. 
Rishi ete 

Thangalai Island, p. 114. PI. 7. 

Thikombia i lau Island, pp. 90, 91, 141, 142. 
Pl 28: 

Thikombia i ra Island, pp. 99, 125, 126, 133, 
136.6 Plc. 

Thithia Island, pp. 53, 96. Pls. 1, 20. 

Thombia Isle, pp. 13, 18, 34, 35, 40, 78, 105, 
106, 107,108. Pls. 4,18. 

Thomson, Sir Wyville, p. 87. 

Thomson, W., pp. 3, 14, 53, 117. 

Thurston Point, pp. 13, 42, 43. 
18. 

Thuvu, Pl. 6. 

Tokalau, pp. 98, 99. PI. 20. 

Tomba Kaivala, p. 32. Pl. 10. 

Tomba Koro Levn, PI. 10. 

Tomba Ndavingeile, PJ. 10. 

Tomba ni Kaseleka, Pl. 10. 

Tomba ni Ndaku, p. 32. PI. 10. 

Tomba ni Richmondi, pp. 28, 29. Pl. 10. 

Tomba ni Soso, pp. 30, 32. Pl. 10. 

Tomba ni Tavuki, p. 28. Pl. 10. 

Tomba ya uravu, p. 30. Pl. 10. 

Tomberua Islet, Pl. 7. 

Tomberua Passage, 
12 EB 

Tonga Islands, pp. 77, 78, 109. 

Tongatabu, pp. 6, 78. 

Tongan Passage, pp. 13, 89, 91. 

Tongoro Anchorage, PI. 5. 

Tongoro Pass, p. 115. PI. 5. 

Totoya Island, pp. 14, 18, 29, 34, 37, 38, 39. 
67, 78, 82, 105, 106, 107, 108, 123, 133, 
136, 138, 140, 143. Pls. 1, 16, 194, 22b, 
23, 66-69. 

Tova Peak, pp. 110. 113. 

Tova Reef, pp. 101, 102, 122, 123. 
23a, 

Trigger Rock, p. 88. PI. 19. 

Turtle Island, pp. 105, 126. 

Tuvana ira, pp. 126, 142. 

Tuvana i tholo, p. 126. 

Tuvutha Island, pp. 13, 48, 51, 52, 53, 70, 
75, 85, 122, 182. Pls. 1, 20. 88, 89. 


Pls. 4, 


pp- 110; 114" ib. 


Pl. 19. 


Pisce, 


Big 
Pl. 23a, 


Unnv Carr, pp. 128, 130. Pls. 1, 4, 17. 

Undui, Pl. 234. 

United States Exploring Expedition, pp. 13, 
88. 140. 


Usborne Pass, p. 30. Pl. 11. 


COMPARATIVE ZOOLOGY. 


Vanvua Kuta, p. 31. Pl. 11. 

Vanua Levu, pp. 6, 17, 18, 41, 42, 71, 118, 
126, 127, 128, 129, 130, 131, 182, 144. 
Pls. 1, 3, 3a, 4, 

Vanua Masi Islet, pp. 69, 125. 

Vanua Mbalavu Channel, p. 13. 

Vanua Mbalavu Island, pp. 17, 35, 47, 48, 
64, 78, 80, 81, 88, 89, 90, 91, 92, 93, 107, 
122, 125, 132, 134, 136, 137, 138, 141, 142, 
148. Pls. 1, 19, 22». 

Vanua Vatu Island, pp. 53, 70, 121, 122. 

BL ape 

Vatauua Channel, Pls. 1, 17. 

Vatoa Island, p. 126. Pl. 234, 

Vatu i ra Channel, pp. 127, 129.130. Pls. 
Sse 

Vatu ira Islet, Pi. 32, 

Vatu i thake, p. 42. 

Vatu lai lai Islet, Pl. 9. 

Vatu Leile Island, pp. 14, 15, 53, 66, 67, 70, 
81, 119, 120, 133, 137, 138, 189,142. Pls. 
1, 9, 17, 22>, 100-102. 

Vatu Levu Islet, Pl. 9. 

Vatuloa, p. 115. Pl. 5. > 

Vatu Savu, p. 68. PI. 9. 

Vatu Vara Island, pp. 48, 53,54, 81. Pl. 19. 

Vavau Group, pp- 77, 78. 

Vekai Rock, pp. 35, 72,123. Pls. 1, 19. 

Vidal, Bishop, p. 96. 

Vienne Bay, p. 130. 

Viti Levu, pp. 6, i4, 17,18, 26, 41, 71, 80,81, 
110, 111, 115, 126, 127, 128, 133, 136, 140, 
144. Pls. 1, 3, 5-7, 20a, 24-45, 

Viwa Island, Mbau, pp. 110, 132. Pl. 7. 

Viwa Island Reefs, pp. 116,117. Pls. 1,3. 

Volcanic Islands, p. 18. 


Pl. 20. 


Vomo Island, p. 117. Pl. 3. 
Vomo lai lai, p. 117. ° 
Vuata Ono Reef, :p. 126. Pl. 23a, 


Vuata Vatoa, pp. 105, 126. Pl. 23a, 
Vuna Point, p. 42. Pl. 4. 

Vuo, p. 182. 

Vuro, p. 31. Pl. 11. 


Vuro lai Jai Island, p. 31. Pl. 11. 


Wasa Isianps, pp. 14, 117. Pl. 3. 

Waikava, p. 128. 

Wailangilala Island, pp. 13, 14, 17, 45, 46, 
47, 48, 49, 53, 69, 70, 72, 81, 83, 101, 122, 
133, 138, 139. Pls. 1, 18, 109, 110. 

Wakaya Island, pp. 13, 23, 25, 29, 42, 82, 
130, 136, 137, 138, 141. Pls. 1, 3a, lla, 
12, 15, 55, 56. 

Walther, J., pp. 121, 134. 

Wangava Island, pp. 52, 
1, 22, 

Washington Cape, Pl. 10. 


53, 70, 133. Pls. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 


Washington Mount, Pl. 10. 

Wharton, Admiral, pp. 8, 138, 75, 104, 106, 
107, 139, 140. 

Wichmann, p. 18. 

Wilkes Reef, pp. 57, 123. Pl. 22. 

Williamson Reef, pp. 13, 34, 40, 88, 100, 107. 
Pl. 19. 

Wilson, Capt.. p. 96. 

Wittgenstein, p. 6. 

Wolff, Prof., p. 106. 

Woodworth, W. McM., p. 16. 


YALE Mount, PI. 10. 

Yambu Island, pp. 31, 34. Pl. 11. 

Yangasa Cluster, pp. 13, 53, 57, 59, 60, 64, 
69, 70, 72, 75, 78, 81, 122, 132, 186, 137, 
139. Pls. 1, 22, 22a, 90-93. 


151 


Yangasa4 Levu, pp. 57, 58, 59. Pl. 22. 
Yanu Yanu eloma Islet, p. 31. Pl. 11. 
Yanu Yanu Island, p. 92. Pl. 19. 

Yanu Yanu san Islet, p. 31. Pl. 11. 
Yanutha Island, p. 34. Pls. 4, 8, 18, 23. 


Yanutha Reefs, Mbengha, p. 26. Pl. 8. 
Yanuya, Pl. 23a, 

“Yaralla,’’ Track of, p. 13. 

Yaroua Islet, pp. 122, 123. Pl. 20. 


Yasawa Islands, pp. 117, 118, 127, 131. 
rte; 

Yathata Island, pp. 14, 53, 54, 123. 
19. 

Yathiwa Island, p. 21. 

Yaukuve Island, p. 31. 

Yaukuve lai lai Island, p. 31. 

Yendua, pp. 127, 128, 129, 131. 

Yuvutha Island, p. 58. Pl. 22. 


Pls. 
Pls. 1, 


Pl. £2, 13. 

13) ipa la 

ied Banal 
Pls. 3, 4. 


ee ee 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 


LIST OF FIGURES IN THE TEXT. 


Deep Bay, East Face of Moala . . 

Northwest Point of Makongai 

edgeofi Makongai . ...... . 

Ledge off Makondranga ..... . 

Storm Islet : 

Nmara and Yanu Yauw lenis 

Western End of Thombia . 

Olorua . : 

Basin of TRetoya Crater, feam the sat of the ‘Northern Rim 
Totoya from the Northeast, distant five Miles . 
Taulalia, Ngele Levu Lagoon. 
Wailangilala and Cakandrovi. 

North Point of Naiau : 

Naiau, seen from the East . ine 
Vatu Vara, seen from the East . . . 
Oneata - at apecuite™ Ne 

Islet off nents ‘Shore 

Yangasa Levu . i 

Southwest Point of Onges byl 
Entrance to Fulanga . 

East Side of Fulanga : Ob ites 
Fulanga South of Quoin Hill . He ceraas 
Southeast Point of Marambo . 

North Point of Marambo eMedia: 
Wiest sideof Vatu Leile . . 9... . 
Northwest Point of Vatu Leile 
Northeast Point of Vanua Mbalavu 
Vanua Mbalavu, looking West . 

Islet off Ngillangillah var 
Volcanic Hills back of Lomaloma . 
Mango, seen from the Northeast 

Mango Landing, Volcanic Substratum 
West of Mango Landing, Volcanic Substratum 
Naitamba from the East ah ae shoe 
Karoni. . 

Northwest Point of Mothe. 

Clipperton Rock . . 

Fringing Reef Harbor, off Koro Levu 
Moturiki Channel . ‘ So uate 
Entrance to Levuka . . . 
Negro-head, Levuka Barrier Reef : 
Levuka A olahoe i, | ae 

Vomo lai lai . : : 

Northern End of Mana 2 


45, 46 


mata 


—~ 
. 


qo 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 15 


EXPLANATION OF THE PLATES. 


PLATE 1. 


Sketch Chart of the Fiji Islands with the Track of the “ Yaralla,” reduced from 
Admiralty Chart No. 2691. 


PLATE 2. 


The same, indicating the position of areas of elevated coralliferous limestones. 


PLATE 3. 


Northern and Northwestern Part of Viti Levu and Southeastern Point of Vanua 
Levu. From Admiralty Chart No. 2691. 


PLATE ‘3s. 


Namena Barrier Reef, Koro, Makongai, and Wakaya Islands. From Admiralty 
Chart No. 440. 


PLATE 4. 


Vanua Levu and Taviuni. From Admiralty Chart No. 2691. 


PLATE 5. 


Southern Coast of Viti Levu from Nasilai to Serua. From Admiralty Chart 
No. 845. 


PLATE 6. 


Southwestern Coast of Viti Levu from Serua to Malolo Passage. From Admiralty 
Chart No. 846. 


PLATE~ 7. 


Eastern Coast of Viti Levu from Suva to Ovalau. From Admiralty Chart 
No. 9065. 


PLATE 8. 
Mbengha. From Admiralty Chart No. 167. 


156 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


PLATE 9. 
Vatu Leile. From Admiralty Chart No. 846. 


PLATE 10. 
Western Part of the Island of Kandavyu. From Admiralty Chart No. 167. 


PLATE 11. 


Eastern Part of Kandavu, Great Astrolabe and North Astrolabe Reefs. From 
Admiralty Chart No. 167. 


PLATE 115 


Sections across. 


Fig. 1. Ngau Lagoon from north to south (Plate 15). 

Fig. 2. Ngau from northwest to southeast (Plate 13). 

Fig. 3. Ngau from west to east (Plate 13). 

Fig. 4. Nairai from west to east (Plate 14). 

Fig. 5. Mbengha from west to east (Plate 8). 

Fig. 6. Viti Levu (Shark’s Peak) across Mbengha Passage, and Mbengha 
(Plate 8) from northwest to southeast (Plate 8). 

Fig. Wakaya from west to east (Plate 15). 


ze 
Fig. 8. Wakaya across southern part of Lagoon (Plate 15). 
Fig. 9. Makongai from west to east (Plate 14). 
Fig. 10. Ono, Great Astrolabe Reef from west to east (Plate 11). 
Fig. 11. Mbulia, from west to east Great Astrolabe Reef (Plate 11). 
Fig. 12. Vanua Kula, from west to east Great Astrolabe Reef (Plate 11). 
Fig. 18. Great Astrolabe Reef from south to north, from Nai Salimu, Kandavu, 
to D’Urville Channel (Plate 11). 
Fig. 14. Solo Rock, North Astrolabe Reef (Plate 11). 


PLATE 12. 
Ngau, Nairai, and Mbatiki Islands. From Admiralty Chart No. 441. 


PLATE 13. 
The Island of Ngav. From Admiralty Chart No. 905. 


PLATE 14. 
The Island of Nairai. From Admiralty Chart No. 9065. 


PLATE 15. 
The Atolls of Wakaya and Makongai. From Admiralty Chart No. 905. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 1b7 


PLATE 16. 
The Islands of Moala, Totoya, and Matuku. From Admiralty Chart No. 441. 


PLATE 17. 


Eastern Point of Vanua Levu, Thikombia to Ngele Levu. From Admiralty Chart 
No. 440. 


PLATE 173. 


Sections across. 


Fig. 1. Vatu Leile, northern end, from west to east (Plate 9). 

Fig. 2. Vatu Leile, centre of island, from west to east (Plate 9). 

Fig. 3. Vatu Leile, southern part, from west to east (Plate 9). 

Fig. 4. Vatu Leile, from south to north to Vatu lai lai (Plate 9). 

Fig. 5. Ngele Levu, from north to southeastern extremity of Lagoon (Plate 17). 

Fig. 6. Ngele Levu, from north to south through Taulalia Island (Plate 17). 

Fig. 7. Ngele Levu, from north to south, east of centre of Lagoon (Plate 17). 

Fig. 8. Ngele Levu, from north to south, west of centre of Lagoon (Plate 17). 

Fig. 9. Ngele Levu, from north to south, near western part of Lagoon (Plate 17). 
0. 


Hig. 10. Ngele Levu, from western entrance of Lagoon to eastern extremity 
(Plate 17). 

Fig. 11. Ngele Levu, west to east, south face of Lagoon (Plate 17). 

Fig. 12. Ngele Levu, west to east, north face of Lagoon (Plate 17). 

Fig. 18. Tuvanai ra, from south to north (Plate 238), 

Fig. 14. Vuata Ono, from south to north (Plate 232). 

Fig. 15. Ono i lau, from southwest to northeast (Plate 238), 


Fig. 16. Vuata Vatoa, from south to north (Plate 238). 


PLATE 18. 


Rambe, northern point of Taviuni, Ringgold Isiands, Nanuku Reefs, Wailangilala, 
to Alacrity Bank. From Admiralty Chart No. 440. 


PLATE 19. 


Yathata to Naitamba, Kimbombo Islets, to Lookout Reef, Exploring Isles, Mango 
to Katavanga. From Admiralty Chart No. 441. 


PLATE 195. 


Sections across. 

Fig. 1. Vanua Mbalavu (Exploring Isles), from west to east to the American 
Passage (Plate 19). 

Fig. 2. Vanua Mbalavu, from west of Lomaloma to Thikombia to encircling 
reef (Plate 19). 

Fig. 3. Vanua Mbalavu, from southeast to northwest across Sovu Islands 
(Plate 19). 

Fig. 4. Totoya, from west to east through Kini Kini (Plate 23). 


158 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Fig. 5. Totoya, from north to south through Kini Kini (Plate 23). 
Fig. 6. From western rim of Totoya to deep water (Plate 23). 
Fig. 7. From northern rim of Totoya to deep water (Plate 23). 
Fig. 8. Koro Island, from west to east (Plate 34). 

Fig. 9. Komo, from south to north (Plate 22). 


Fig. 10. Komo, from west to east (Plate 22). 
Fig. 11. Komo, from southeast to northwest Passage (Plate 22). 


PLATE 20. 


Thithia, Tuvuthé, Thakau Tambu, Naiau, Reid Reef, and Northern Part of Argo 
Reef. From Admiralty Chart No. 441. 


PLATE 20:, 
Sections across the Barrier Reef of Levuka Harbor. From Admiralty 
Chart No. 1244. 


Fig. 1. From the shore of Ovalau through north entrance (Plate 7). 
Fig. 2. From the shore of Ovalau across Lekaleka Reef, about half a mile south 
of north entrance (Plate 7). 
Fig. 3. From the shore of Ovalau across Lekaleka Reef, about three quarters of 
a mile north of south entrance (Plate 7). 
Fig. 4. From the shore of Ovalau to the Beacon, Levuka, through the south 
entrance (Plate 7), 


Fig. 5. From Naquima Point across Mbalavu Reef (Plate 7). 

Fig. 6. Reid Reef, from south to north across the islets (Plate 20). 

Fig. 7. Reid Reef, from south to north (Plate 20). 

Fig. 8. Reid Reef, from south to north (Plate 20). 

Fig. 9. Reid Reef, from west to east (Plate 20). 

Fig. 10. Argo Reef, from south to north to outlying reefs (Plates 20, 21). 
Fig. 11. Argo Reef, from south to north (Plates 20, 21). 

Fig. 12. Argo Reef, from south to north to passage (Plates 20, 21). 


Fig. 13. Argo Reef, from west to east (Plates 20, 21). 

Fig. 14. Ovalau, from flat to westward to Barrier Reef (Plate 7). 
Fig. 15. Longitudinal section across Nandronga Harbor (Plate 6). 
Fig. 16. Fringing Reef, north of Tandola (Plate 6). 

Fig. 17. Incipient Barrier Reef north of Likuri (Plate 6). 

Fig. 18. Tova, from south to north (Plate 23). 

Fig. 19. Tova, from west to east (Plate 23). 


PLATE 21. 
Vanua Vatu, Lakemba, Argo Reefs, Aiwa, Oneata, Thakau Lekaleka. From 
Admiralty Chart No. 441. 


PLATE 22. 


Olorua, Thakau Vuite, Komo, Mothe, Thakau Motu, Thakau Vau, Wilkes Reef, 
Wangava, Kambara, Namuka, Yangasa, Thakau Levu to Thakau Naso- 
kesoke, Fulanga, Nuku Songa, Ongea, Marambo. From Admiralty Chart 
No. 441. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 159 
PLATE 228. 
Sections across. 
Fig. 1. Naiau, from west to east (Plate 20). 
Fig. 2. Kambara, from west to east (Plate 22). 
Fig. 3. Mango, from west to east (Plate 19). 
Fig. 4. Fulanga, from southwest to northeast (Plate 22). 
Fig. 5. Fulanga, from west to east (Plate 22). 
Fig. 6. Ongea, from west to east (Plate 22). 
Fig. 7. Ongea, from south to north (Plate 22). 
Fig. 8. Yangasd, from northwest to southeast (Plate 22). 
5 Fig. 9. Yangasd, from south to north to passage into Lagoon (Plate 22). 
; Fig. 10. Oneata, from south to north (Plate 21). 
Fig. 11. Oneata, from west to east (Plate 21). 
Fig. 12. Oneata, from south to north to passage into Lagoon (Plate 21). 
: Fig. 13. Aiwa, from southwest to northeast (Plate 21). 
Fig. 14. Aiwa, from south to north to passage into Lagoon (Plate 21). 
| Fig. 15. Aiwa, from west to east (Plate 21). 
Fig. 16. Adolphus Reef, from west to east to passage into Lagoon (Plate 18). 
Fig. 17. Adolphus Reef, from southeast to northwest (Plate 18). 
Fig. 18. Nuku Mbasanga and Nuku Mbalate, from west to east (Plate 18). 
PLATE 22». 
! Diagrammatic sections showing hypothetical changes due to erosion and sub- 
marine denudation of some typical islands of Fiji. The dotted lines indicate 
P the assumed outlines of the ancient islands. 
' Fig. 1. Nairai. 
Fig. 2. Makongai. 
Fig. 3. Wakaya. . 
Fig. 4. Mbengha. 
Fig. 5. Great Astrolabe Reef. 
Fig. 6. Tuvana i ra. 
Fig. 7. Fulanga may have been elevated either at the rim or have been a 
dome-shaped mass. 
Fig. 8. Ngele Levu. 
Fig. 9. Ongea. 
Fig. 10. Vatu Leile. 
Fig. 11. Oneata. 
Fig. 12. Vanua Mbalayu. 


Fig. 1. 
Fig. 2. 
Fig. 3. 


PLATE 23. 


The extinct Crater Totoya. From Admiralty Chart No. 1248. 


PLATE 238, 


Onoilau. From Admiralty Chart No. 742. 
Tuvanaira. From Admiralty Chart No. 742. 
Vuata Ono. From Admiralty Chart No. 742. 


160 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


Fig. 4. Vuata Vatoa. From Admiralty Chart No. 742. 

Fig. 5. Tova Reef. From Admiralty Chart No. 742. 

Fig. 6. Thakau Momo or Horseshoe Reef. From Admiralty Chart No. 741. 

Fig. 7. Penguin Bank. From Admiralty Chart No. 1431. 

Fig. 8. Na Ndongu Reef, north shore of Vanua Levu. From Admiralty Chart 
No. 440. 

Fig. 9. Nukui ra Reef, northwest coast of Vanua Levu. From Admiralty Chart 
No. 379. 


Fig. 10. Thakau Moi, north coast of Viti Levu. From Admiralty Chart No. 379. 

Fig. 11. Laukoto Reef, northwest coast of Vanua Levu. From Admiralty Chart 
No. 379. 

Fig. 12. Thakau Levu, northwest coast of Vanua Levu. From Admiralty Chart 
No. 379. ‘ 

Fig. 138. Section across Penguin Bank. From Admiralty Chart No. 14381 


PLATE 24. 


Barrier Reefs forming entrance to Suva Harbor. Namuka Island and Moivuso 
Point on the right. Mountains from Serua to Nimosi District in distance. 


PLATE 25. 


Barricr Reef across Lauthala Bay. Nukulau and Mokaluva Islands in distance. 


PLATE 26. 


Barrier Reef Flat, west side of entrance to Suva. Mountains of Nimosi District 
in background. 


PLATE 27. 


The same Reef Flat as Plate 26, extension to line of breakers. 


PLATE 28. 


Pocillopora Flat Barrier Reef, east side of entrance to Suva. 


PLATE 29. 


The same as Plate 28, extension of Barrier Reef, Pocillopora Flat, to the South. 


PLATE 30. 


Channels dug by Echinometra lucunter. Barrier Reef Flat on eastern side of 
entrance to Suva. 


PLATE 31. 


Elevated Limestone Bluff northeast of Suva, distant seven eighths of a mile from 
Government Wharf. 


PLATE 32. 


Elevated Limestone Islet. Inner Harbor of Suva. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 161 


PLATE 33. 


The Island of Ovalau seen from the east. 


PLATE 34. 


Levuka (Ovalau) seen from outside the Barrier Reef. 


PLATE 35. 


Flats of Volcanic Mud to north of channel of Barrier Reef, looking southwest from 
Mbau. 


PLATE 36. 


Viwa Island, Mbau Waters, composed of stratified volcanic mud. North of channel 
of Barrier Reef. 


PLATE 37. 


Nasilai Barrier Reef seen from the east. Negro-heads of elevated limestone. 
Nasilai Light in distance. 


PLATE 38. 


Nukulau and Mokaluva Islands seen from the southwest. 


PLATE 339. 


On north shore of Nukulau Island, elevated limestone beach. 


PLATE 40. 
Nukulau Island Barrier Reef Flat from the southeast. Negro-heads, elevated 
limestone. 
PLATE 41 


Nukulau Island Barrier Reef Flat, extension to line of Breakers. 


PLATE 42. 


Fringing Reef Flat off Koro Levu, east coast of Viti Levu. Negro-heads, volcanic 
rocks. 
PLATE 48. 


Fringing Reef Flat south of Singatoka River. Elevated limestone outliers along 
the shore. 


PLATE 44. 


Sand Dunes north of Singatoka River, Fringing reef has disappeared. 


PLATE 45. 


South Point of Thuvu Harbor. Elevated limestone and fringing reef. 
VOL. XXXIII. 11 


162 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


PLATE 46. 
Volcanic Cliffs, East Shore of Mbengha, near Solianga Village. 


PLATE 47. 


Shore Bluff, Volcanic Breccia. Rukua, west shore of Mbengha. 


PLATE 48. 
Highest Ridge of Mbengha, volcanic, seen from Moturiki Bay. 


" PLATE 49. 
Western Point of Storm Island, eastern edge of Mbengha Lagoon. 


PLATE 50. 
John Wesley Bluffs, Kandavu Island, volcanic. 


PLATE 51. 
Northwest Side of Ono Island, volcanic, inside of Great Astrolabe Reef Lagoon. 


PLATE 52. 


Yaukuve lai lai Island, voleanic, seen from the west, inside of Great Astrolabe 
Reef Lagoon. Ono in the distance. 


PLATE 58. 
Solo Rock Lighthouse, North Astrolabe Reef Lagoon. 


PLATE 54. 
Solo Rock, volcanic, North Astrolabe Reef Lagoon. 


PLATE 55. 
West Face of Wakaya Island, voleanic. Surf on Fringing Reef. 


PLATE 56. 


North Shore of Wakaya Island, volcanic, forming south side of Boat Passage lead- 
ing into Wakaya Lagoon. 


PLATE 57. 


Looking into deep Bay on east side of Moala, volcanic, from outside of Barrier 
Reef. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 163 


PLATE 58. 


Southwestern side of Nairai, voleanic, seen from Anchorage inside the Lagoon. 


PLATE 59. 
Kobu Island, volcanic (Magnetic Island), inside of Nairai Lagoon, seen from the 
north. 
PLATE 60. 


Islets (Mbuimbani to left) off north point of Taviuni Island, volcanic. 


PLATE 61. 


Kimbombo Islands seen from the east, distant two and a quarter miles; to the left, 
Volcanic Island, and Elevated Limestone to the right. 


PLATE 62. 


Eroded Shore Line, Volcanic Rocks, Islands of Lau. From a Photograph by E. G. 
Jones, Esq. (Thithia teste Andrews.) 


PLATE 63. 
Northeast Point of Komo, Volcanic Rock Outlier. 


PLATE 64. 


Beach on the North Shore of Komo, Volcanic Rocks, Komo Ndriti in the distance. 


PLATE 65. 
Pocillopora Fringing Reef Flat, Komo Island. 


PLATE 66. 


East Rim of Totoya, seen across the Isthmus, inside the Lagoon of the Western 
Coast of the Island of Totoya. 


PLATE 67. 


Opening into the Totoya Crater Basin, seen from the West approaching the 
“ Gullet,” inside the Lagoon. 


PLATE 68. 
Islets to the West of the “ Gullet,” looking into the Totoya Crater Basin from the 
Entrance into the “ Gullet.” 
PLATE 69. 


Islet off the Inner Edge of Northern Rim of Totoya, seen facing the Eastern Inner 
Rim of the Crater. 


164 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


PLATE 70. 
Eroded Rim of Crater Basin of Thombia, Budd Reef Lagoon, Ringgold Isles. 


PLATE 71. 


Crater of Haleakala, Hawaian Islands, from a height of about 2,000 feet on the 
edge of the rim. 


PLATE 72. 


Northeast side of Vanua Mbalavu Island, seen from inside of the Lagoon. The low 
ridge along the shore consists of elevated limestone, also the conical hill to 
the left; the rounded hills in the background are part cf the volcanic nucleus 
of the island. 


PLATE 73. 


Northeast Point of Ngillangillah Island, inside Vanua Mbalavu Lagoon, seen from 
the East. Elevated limestone. 


PLATE 74. 
Cafion, east shore of Ngillangillah Island, Vanua Mbalavu Lagoon. Elevated 
limestone. 
PLATE 75. 


Avea Island (600 feet). Vanua Mbalavu Lagoon. Elevated limestone. 


PLATE 76. 
Alcyonarian Flat, Ngillangillah Island. 


PLATE 77. 


Limestone Bluff north of Tokolau Beach, Kambara, Wangava in the distance. 


PLATE 78. 


Volcanic Hill south of Tokolau, Kambara. The elevated limestone extends to the 
valley on left of hill. The negro-heads and shore platform underlying the 
limestone are volcanic. 


PLATE 79. 


Elevated Limestone Cliffs, Northwest Shore of Kambara. Neither fringing nor 
barrier reefs along this part of the coast. 


PLATE 80. 


Southeast Side of Fulanga. High hills in the southeast corner; shore line of low 
limestone hills in the foreground, seen from outside of barrier reef. 


_ 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 165 


PLATE 81. 


Looking into Fulanga Lagoon and Sound. Limestone islets across the rim of the 
Sound. Limestone islets and hills in the distance. 


PLATE 82. 


Entrance into Fulanga Lagoon and Sound, seen from the east. 


PLATE 83. 


Limestone Islets in Fulanga Sound, and Islets across eastern Margin of Sound. 
From a Photograph by Mr. Hathaway. Limestone Bluffs of Inner Rim of 
Sound looking east. 


PLATE 84. 


Undercut Limestone Islets in Fulanga Sound. From a Photograph by the Hon. 
W. L. Allardyce. 


PLATE 85. 


Low Gap, looking across Barrier Reef, into closed Sound of Northeast Coast, Mango. 


PLATE 86. 


Elevated Limestone Bluffs, East Coast of Mango. To the right along the beach 
the volcanic rocks underlying the limestone crop out. 


PLATE 87. 


Volcanic Islets on the southwest side of Mango, on the edge of the Barrier Reef. 


PLATE 88. 
Northwest Point of Tuvuthd. Elevated limestone (800 ft.). 


PLATE 89. 


Southeast Point of Tuvutha. Elevated limestone. 


PLATE 90. 
Yavutha Island (240 ft.). Elevated limestone, distant 1} miles from the southeast 
inside of Yangasda Lagoon. 
PLATE 91. 


Looking into Bay on north side of Navutuiloma Island, Yangasd Lagoon. Ele- 
vated limestone. 


PLATE 92. 


Point (elevated limestone) on North Shore of Navutuiloma, Yangasa Lagoon. 
Yavutha Island in the distance. 


166 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 


PLATE 93. 


Islets (elevated limestone) in Bay of Navutuiloma, Yangasdé Lagoon. 


PLATE 94. 
North Shore of Ongea Ndriti (elevated limestone). 


PLATE 95, 


Taulalia Islet, distant two miles, northern edge of Ngele Levu Lagoon. Seen from 
Anchorage inside of Lagoon. The cones are composed of elevated limestone. 


PLATE 96. 


Northern Point of Tai ni Mbeka Island, elevated limestone, northern edge of Ngele 
Levu Lagoon. 


PLATE 97. 


Pitted and Honeycombed Surface of central part of Ngele Levu Island, with typical 
inland vegetation. 


PLATE 98. 


Pitted and Honeycombed and Denuded Surface of Ngele Levu Island near eastern 
shore, with conical mounds and deep crevasses. 


PLATE 99. 
Vegetation, West Shore of Ngele Levu Island. 


PLATE 100. 
Elevated Limestone Bluffs, Northwest Shore of Vatu Leile, seen across barrier reef 
line. 
PLATE 101. 


Vatu Savu Islets (elevated limestone) on northern edge of Vatu Leile Lagoon. 
The low eastern shore of the island of Vatu Leile (elevated limestone) in the 
background. 


PLATE 102. 


Vatu lai lai Islets (elevated limestone) northern rim of the Vatu Leile Lagoon. 


PLATE 103. 


Southern Horn of Nanuku Levu, seen from the south. Nanuku Levu Island in the 
distance. 


PLATE 104. 


Nanuku Levu Island, seen from the west across the Western Reef. 


AGASSIZ: FIJI ISLANDS AND CORAL REEFS. 167 


PLATE 105. 
Southern Reef Flat of Nanuku Levu Island. 


PLATE 106. 
Beach Rock on East Shore of Nanuku Levu Island, 


PLATE 107. 


Negro-Heads (elevated limestone) occupying Position of Nanuka lai lai Island. 


PLATE 108. 


The Islands of Nuku Mbalate and Nuku Mbasanga, seen from the west across the 
encircling reef. 


PLATE 109. 


Western Point of Wailangilala Island, distant one third of a mile from anchorage 
inside the Lagoon. 


PLATE 110. 


Northeast Point of Wailangilala Island, seen from Lighthouse Tower. 


PLATE 111. 
Southeast Horn of Thakau Lekaleka, Oneata Passage. 


PLATE 112. 


Northeast Horn of Motua lai lai, seen from the east. 


a 


— 
4 


MAMAN UTHA,S. 
TSLAND 5 


VatuLeilg 
i) 


SOUNDINGS IN FATHOMS 
Track of the YARALLA 


sono 50M? = 


ay 


Namena Barr Reef 


jakongai 
ine 


Horse Shoe Reef 


ange 


FIJI ISLANDS 


REDUCED FROM 
ADMIRALITY GHART N° 2691. 


pik ISLANDS 
yntinnation of Group. 
manaatono 


RO 
vue tN 


Donoiraw 
=o 


FEXPLOWIXG ISLES 
dee 


=. 
DMolevuvu Reef 
vy 


ty akan Tambu 
S oB 


BPs vers 
Ly 


Vou tel 
aton or Turtle 1 


B Mesa) bith. 


—* 


ne 


ikonibia 
— 
a2 5) 


are SE 


er cir = s FLJI ISLANDS 
se —_ : oh 


REDUCED FROM 


ADMIRALITY CHART N? 2691. 


ange 


Pi — Naan. © wis ee 


Malima Is@),, 


= 
Yathatngges 


a 
Vatu Vara ® DB Molevuvo Reef 
»"t : P ma) ¥ 
MAMAN UTH Ag : . : } aoktafanga 
Isuanps "= | By va 3 : f ey arnge 


Morse Shoe Reet 


Nairai 
Ties) 


Vataleile 


Seu 


e AK | 


Mavuku, 
fzea) 


SOUNDINGS IN FATHOMS. 
Blevaled limestone colored. -—_= 


B Meisel jth 


FIJI ISLANDS AND CORAL REEFS. 


m7" 


Soundings in fathoms. 


MAMANUTHA 
ISLANDS 
(Hudson I*) 


ao 


e 


wa << 15 
San ogy 
<S gy Mntated 
Nathoulla yAod Asawa. 
Ethel Reefs Jadeia. S| 
od ‘, e 
; MSt.° 


Full of Coral patehes 


road Tisemage 


a it 


~ Djiistrict 


oRoru Ei 
T 


eG 
Solo Ira Joi Roni 
q District 


Drawunt 


PK pA samara 
¥. va ss ee 


wn) 
frongs Dietei ve 


Foro i vatue 


THE HELIOTYPE PRINTING CO,, BOSTON 


as 


me 


= 

- 
. 
a 
Ag 
: 


A 19 


~* aro 


@iesK fedrd 


FIJI ISLANDS AND CORAL REEFS Pi. 3® @ 


Barrier 
‘4 


Soundings in fathoms 


THE HELIOTYPE PRINTING 


FIJI ISLANDS AND CORAL REEFS 


8° 


wr nroyp eminem 
oe mand indie C 
14 ey a 

wae illo 


10 MILES 


Soundings in fathoms 


THE HELIOTYPE PRINTING C0, 8O8TON @ 


24898 IAROD as 2d 


> 


i» a | 
a 


1G 
ose 


aoe 


a 


ee al 


PL.5. 


FIJI ISLANDS AND CORAL REEFS 


NASILAI TO SERUA. 


SURVEYED BY LIEUEY W.U. MOORE, B.N, 1676-7. 


wasicarl 


SOUNDINGS tm FATHOMS. 


Sis (rom 600 t» 1000 feet Righ 


* Donets! erated Ditty, Prem (00 & 1000 feet high 


| 
Soundings in fathoms. | 
| 
| 


Pr 5 MILES 


ré40 


THE HELIOTYPE PRINTING 00,, BO4TOW 


o yy 
cord 
¥ fy" 


24HaH JANOD GMA edqMa, 


er & 


a mat 


h 
i 


; oe 


ee 


a 


- 


s 
pas 


et 
<€ 


— = 


Pu. 6. 


FIJI ISLANDS AND CORAL REEFS 


zt 


é : i. fe Broken ranges 1000 to 2000 FF 


SERUA TO MALOLO. 


ulating cauntny epvered 


with grass and sorewpines 


Disitrict 


oe | 


Leghtty timbered 


7 Serna Digtrive 1 
- P- + NE tay 


Soundings in fathoms. 


5 MILES 


THE HELIOTYPE PMNTIND COL, BORTOR 


¢ 24A 00 Bek 


) QUA 2a 


24YSaA AARO 


FIJI ISLANDS AND CORAL REEFS. 


= Aaalhoany 


a me 


Nar terns 


ee 9 a 


aT) 


Soundings in fathoms. 


nT el 


i 


ea eros 
po aA es © 


a 


FIJI ISLANDS AND CORAL REEFS. 


Frigate Passage 


THE HELIOTYPE PRINTING CO., BOSTON 


#4 Foul Ground™ 
s Py 


Soundings in fathoms. 


5 MILES 


THE HELIOTYPE PRINTING GO,, BOBTON 


. > 
, 
oy TITS 
- - 7 - 
_— _ * <a 4 
ame x 4s 3 et ag ote ; . tz 
Petre, fk j he ve = “nl 
ty . bas # vad . - 
+. See ee Tate gen. 5 
tial sf > -, (heer eho ‘ 
a * ‘ wa 4 /s 4 “4 ng oe 
3a ¥ si, aN JPY a: . ¢ 
. i ae hie eee Bs 
5 5 : ‘ - an + 
te * 4 
+ a 7 
" , ¥ 
~ ’ . 
eso, 
+ 
m 
, 
( 
we 
. 
Naa 
. 
‘ 
® —— * 
a = ——— ne i’ 


FIJI ISLANDS AND CORAL REEFS. Px.9. 


VATU LEILE To 
( Flood, rune S.S.6. Ebb NNW) 


Soundings in fathoms. 


5 MILES 
d 


THE HELIOTYPE PRINTING CO,, BOSTON 


FIJI ISLANDS AND CORAL REEFS. Pr. 10. 


Alaceity Web) e's 


Malatta 


Reefs 


he 


| 

ato 
178'20" 

Soundings in fathoms. 


THE HELIOTYPE PRINTING CO., BOSTON 


jerka ch conned 


FIJI ISLANDS AND CORAL REEFS. Pi. ll 
Le. Li. 


North Astrolabe Ree?’ 


5 MILES 


hago’ 18°40 


THE HELIOTYPE PRINTING co,, BOSTON 


ee: 


ni a 


oe 


PAE aay Tere Cet iee 60g MOPED 


soo fl 


4 
VY age fl ¥, 
13 
XK Ono N Soundings in fathoms 


2 Sea Level 
Nai Salimu = ————”_ Heights in feet 


s 


soft 


wooft 


SE 


yao Tt 
Sea Level 
+ “ 2 7 ir 
Sea Level Yanutha 
= WV K é z 


Mbengha 


160 ft 


Solo Rock 


Sea Level 


Sharks Peak 


500 
sao ft 
6 10 
Mbengha Passage 
Sea Level Sea Level 
~ = es © / 
iF 7 wi 
7 1) - 


Mbengha 


North Asrolabe Reef 


Ono 
wo fl 


Astrolabe 
876 Et 


Ww 


sat 


ud Mbulia 


Great Astrolabe Reef 


Ww 260 ft 


9. 


Sea 


12 


Level 


Vanua Kula 


Great Astrolabe Reef 


100 
alay 


nf 
one 
seh 
oo 
j 
‘ "oF “ 
~ =< / ae de 
5 ~ = pes 
¥ & um @e 
foes flonan 


See 


Nw ou Le ah ty 


Thaw 
¢ 
von ANAS 
Te oe: ee ot “ TY 
i gee 


iit PY ae 7 ae 
pe ee 


sqnek aS PAH way 


en 


Aer oleae 


Graal halt 


\ 
apogee, al 


Wakaya 3) 


(See vlare 1260) 5) 


zio 


FIJI ISLANDS AND CORAL REEFS. 
179" 


etalk 
(see plar. 741) 


VES Sprise 44% 9 hp 


dra hi 


1 
+ PP%. 240 
2575, \Thackaus momo| Horea Shoo R’ ) 
(See plat 741 
ow ‘mash 


410 


Pu. 12. 


sso 
72° NAIRAL (Secplan 741! 
W*  -VE5S™ Sprine TEND SET 


o/ Boar. Bra™} 


18" 


aio 
} 
763 280 co 5 MILES 
gos — 28, 
260 NGAU I. 
(See plan 1251) 
280 VIB 7 Spwrise 5f¢Np.34 7 
280 
a or Cocoarust I. 
wo ait 
380240 = 
x0 

753 
ae SE 

, = 230 ato yp 

Soundings in fathoms. 23 gon 
| ‘of 78 
MambulithaReefy =m peti A stots oe 
see plar. 1251/ ob 
190 
a 


179° 


i 
/ 


a 


FIJI ISLANDS AND CORAL REEFS. "Pr. 13. 


= ae 
Se Ona 


vie MATUB URA 
zo 
ma 
NaMbukebu 
2 
NGAU ISLAND 
(See plar. 1242 } 


VE 7* Sprise Sf Np.32* 


Forest P¥ just open tothe} 
South of Orasey P¥ (NOTE. { 


179°20° 


Soundings in fathoms. 


S MILES 
ee Se 


a) 


THE HELIOTYPE PRINTING CO., BOSTON 


FIJI ISLANDS AND CORAL REEFS. Pu. 14. 


179 20 


ne 2s 
a 240 
230 
= HORSE SHOE REEF 
(Cakau 0) 
ovash’ ‘awash, ‘See plan 741) 


5 Mites 
— — 


ai 1 — —______1_— 


1740 


we + Bde 
n 29$ 7% NALRAL (See plan 741) 
34 VS¥" SprineaiftNp si 


ato 


et 


cs oO wt 
“EOB Ss 
bul 
_ oP7s 
ee 
q 
4 
t 


17920" 


Soundings in fathoms. 


THE HELIOTYPE PRINTING 0O., BOSTON 


—eres 


FIJI ISLANDS AND CORAL REEFS. 


° 


179 


MAKONGAI VI 0® Sp.rise 4f*Np ort 
(See pianiz50! 


Soundings in fathoms. 


R, ato 
1740 i a Te 
SMILES 


THE HELIOTYPE PRINTING CO., BOSTON 


500 
om 


Pu.15. 


eso 
oz 


“ pews touching 
S.59°W leads to an orarrce 


FIJI ISLANDS AND CORAL REEFS. 


260 


1795 


mn 


By 


ao 


@ 


106 
oe 


2625 
ale gio 


4780 


elagios 


MOALA (06 piani952/ 


VASO" Spruce 547 
| 


phos i} 
a = Se 
apdo 
sao 
Blow | 
oo 
ne 


fakouka. 8 
ato MATU KU (See pian i297 
TEIB™ Sprise BO Mpa IT 


480" 


THE HELIOTYPE PRINTING CO., BOSTON 


Soundings in fathoms. 


Px. 16. 


FIJI IST 


NDS AND CORAL 


150° 


D225) Pt. 17, 


aio 4 
io 25 
260 
ato 
Pe 
Beown Passage P61 
: 2a, A ear: 
250 ” (39% 
a ‘. Me. 
> Deep passaji® 
- a0 aio. 
#0 = . 
aio a 
sho abo 
iho 
ado 
wo Pe 
wo 6S 
E ao 
» 
Ss abo 
ago %e 
ado s <t to 
5 MILES 
" ree Sey 
260 


180° 
HE HELIOTYPE PRINTING CO., BOSTON Soundings in fathoms. 


orth end 


Leile 


e 


—— 


2 


a 5 
son soft 
aes Level 


Ngele Levu 


100 
100 


ae se Level 


Ngele Levu 


100 100 


Sea Level 


PLATE 


178 


Vuata Ono 


Sea Level 


Vuata Vatoa 


2 
Vatu Leile (Centre) 
Ww E 
3 
7 
Southern part 
4 
\ 
Vatu Leile 
5 
100 
10 
eee Se a Level == = = —_ ~ 
i 7 7 
a Ngele Levu (Longitudina 
¥, 
j00 / 
i 
Sea L ‘ i 
] ; 
(South face Levu 
Ww E 
2 
7% bevel __ 
= WV Sas 
(North side) Ngele Levu 
W E 


* Vatu Lailai 
x J mile 
oo ? 2/5 
ir avy. Saft Figs. 13-16, 
Ew Kon aoe 
Ono i lau 


7 nule 
+ 4 ep, 
Figs. 1-42 


Soundings in fathoms 
Heights in feet 


N 


bth. 


(hs sted) “efi oR ete Views 


An 


4 
bd se ia , ~“ 
ie Bie ice 2 3G. 
a. a 
- > Ts c 


iswasd) o9fi5.t 1 ev 


a Na¢@in ieee 
nee 
“> wy 
7 
ey cece a 
Le ~~ em 4 
; ee, “se% 
; ( an otha 4, 
i, “oT kee a 


x -— + 4 , 


7 J Va Le tome La 
: 


»+ Lro.t winsV¥ \ 


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a ao PR ee ee ee ee ne 
> Ww ii 


1 
MB rnet! ove d ee a ih 


be 


ee 


f suo) glo UM igre? Hino 

’ Oa 

war fon / 
$ 
f y \) Baas a : SS : - 
J bo 
ova sloyt (obras atv0%) 
vba ‘Gee be wm 
Lista) 


FIJI ISLANDS AND CORAL REEFS. 


we 


wo 
“ 
| 20 
| to 
| ao a 
| 20 
eae 
- an 7g HENS I 
| 1gF.1i 
3 a 
oa sto 
no eo 
oP 0 
74 an 34 


2a J 
oe 
abo RINGGOLD CHAN. “\ 
, e 
ato as 
a. ao Budd Reef 
vy 
} 230 aio 


400 


360 
‘ Hs Miller At xs 
ko A Ed 4 380 Breke haanpy CS 
Mt. ry 
a Re wo 
80 aed a asa 9 Song FS 
alo Breaknot BM" @ 40 43974, 44 Syl> r. 
D Wb E48 46 4 yr 
- ue ps 
ail m1 
sab oy 5s 
2fo we 
ge* ako 
0K 
wh VS ay 
epee £ 
wa * “g 
bo 
aio 
uo 
ato 
aot 
pio 
ato 
5 MILES 
= on 
TAVIUNI io o + 
Dread with dowds in SE. tnt a 


THE HELIOTYPE PRINTING 00., BOSTON 


Fo 


230 


oa 


ae 


TOF high 


79+ 
glo 


Nuku Mbaninga 


Covonrraute Snes | 


20 


y 


738 
ohm 


fy 
s 
Fo 


305 
in 


aie 


mm 


731 
vole pt 


| Wo 


50 


Soundings in fathoms. 


Pt.18. 


@* 
[ « 


d 
2 J 

ia” 
weg 
4 - 

na 


& 


—_——e + 5 
q . 


gf 


: 


> 2 - 
ea mie 


par. 


_— 


ee 
ee 


f 


pert ee eT 


a Pr, 19, 
FIJI ISLANDS AND CORAL REEFS. S 


776 
ae 
tte 
535 
as 
35 
b 
Bo 
280 
as 
150 
255 
ato , 
Nuku Thikom bia. R 
FOB (Corul dry at low tide} 
ai6 a 
abo 
300 6, was 
ee Islets se. 
an Ve 
Palin gf 
27) 
cet 
Kanathea (630) 
(Densely wooded) roatghs! EXPLORING 
a 
fo a7 | * 3,77 Ou * = 
|= 2 inte Ee ISLES 
9," 29 fT, 1 18 20 
us avs 22 8 ae By Gar * G18 
WE a a 2 ee 
abo oe a2 16 
43t 200 
Se 
bo 300 
bo 
i te 
Py ty 
thigh Ro * eat sto 
(Wert) Vatu Vara rost Rt % 
Tensdly wooded} ed bs ie 4 zbo0 
Tix) 


5 MILES 


THE HELIOTYPE PRINTING Co,, BonTON 


179° 


Soundings in fathoms. 


, we :. 
Meet robes PF, ce 
“= - 


oo ‘- - 


; » GE es 
. May 3 Ae Ar. p Aust 
7 bine 1 wr 
> 4 nt | 
A y 
: hs, . a... 
a od 
. * 
mm 4. —- m4 
“ oe @gBak Pureage Js 


. Gu 


cas, sd exxenal 
Serena my terete 


.f 


Ful [Stanps 


PLATE. 19% 


2t0 ft 


93oft 9 


Sea Level 


Komo 


too 


: nerican Passage 
Vanua Mbalayu American Passag 


sooft 


106 
2 3, miles 5 
Figs. 13, 8-1. 
3 
z i Thikombia 1 lau 
Wy, Vanua Mbalayu 4 +l) 
too 6 
a goo fl 
zsfl 
3 
= Sea Level _ ) x Sea Level 


Tr 
Imerican Passage 


isnot 


4oft 


44 mile 


Ww 


énaft 


Soundings in fathoms 
Heights in feet 


Kini-kini 
J mile Toto Maks 
eel plat 


Figs. 4,5 W. Kove 


soo ft 


- Sea, Level 


rotoyva Kini-kini ae 


mile. N 


B Meisel hth. Brsten, 


tates £20R 


‘wr 


/i Xe 


a ae ah a i " a Z soe J 
— : _ i hed 7 a. 
r Ae: “ ot . jf ‘ ' > 
. ‘ i nemer “al emelomol, > Se 
‘@tadM nL ed 
* \ 
esol Oe 
" , ba ¥ 
4 49) nok wee. toe 
aad canine catlepasenns epraanagieed donates o 
¥ “Se \ ¥ z ; a 
oo “Senter noi, © \ t 
d ; = : 
Vw. }\ 
aot ; Dveta dy ni Asy 
4 po 
. \ 
i ‘ f 
: \ 4 - 
26 4 
eae 
J A 
f \ 
j ey 
f * 
REO OSS SI RRR pent ee 
i ¢ = Vs ee 4 e? 
‘ 2¢ * ee 
% a 
itiAc-parh 
Fn " v o!lo a awe « 
es BYre 
arf 
*Y 
NN 
™~ 


4 reiemaarerat .. b 


AND CORAL REEFS. Pu. 20. 


179" 


0 
F am, 

Te vonua, J gandocy (4Fthigh) 

(Satadt ot pest and P00 


a 
Thakau Lasemarawa 
9 (Haakine Bf of Wilkes) 
a 


Maat Rog, 2 


woaTO. 


18° 


Soundings in fathoms, 


Northern Part of Argo Reefs. 


179° 


THE HELIOTYPE PRINTING CO,, BOSTON ¢ 


2% 


_ dibs . 
_ S See 2. ee OB Ree Ae 


—) os) a 


DS AND CORAL Reers 


if 
Late i Tonga Late 1 Vili 
soft See Level ree } Se a ee North Entrance Levuka Harbor Sea Level 
<< = er — TK >= T 
1" u 10; 
rs > Casi 
T 
Reid Reef “ watt a = Ka 
N. \i00 yon 7 
Sea Level J Sea Level 
= Ld e 100 
Reid Reet - Levuka Lagoon a8 kaleka Reef screed 
N Argo Reef s i 
io é A 
100 = 7 3 13 
7 4 
i 
Reid Reef l2. isa BE eieL Aan é 
100 1 3 ae 
25 30 Lekaleka Sea Level 
- _- —— S Argo Reef N 
= - 7 300 
foo: |! ST aks ee gw | Pk ee ee ee ee SS |; eee 
Reid Reef 
ios ft 
— _ = nae a__Levet a ce S 
7 < South Entrance ~ 
> = zs Levuka ; 
27 Ty 2 ETT ——— = = = 
a Ar ; : E : : 
woot Reet 3 miles r90 Sea 
Figs. 6-13. aa - 
1S. Sea Level : = 
? e- 
7 PS 
Nandronga 
Soundings in fathoms 14. 
: too 
Heights in fect 16. 18. ahi 5. . 
Sea Level at 4 iv ~~ Sea Level Peta e 
Wi =a — J z Levuka Lago G Mbalayvu Reef _ Sea Level _ 
7) 
i 
Nof Tandola Tova a 
i mile 
Ovalau 100 Figs. 18-19 oy ans=s>= = 
i £ 17. 1 . ) 
Sea Level ; 3 
ee Sea Level i 
: _Sea = mile 77s: Ze 
Sa Ce 
ae 7% mile. r 
a Nof Likuri 
miles. Tova 


Figs 14-17 


tov 


B Meisel hth Bosee 


ee 
a 
® S 
ave 
a 
4 
Ux 


i» 


bey Phd cot abl toint 
Ne 


ee bs 3 | 


x \ 2am OAN\ 95 eqestameg " 
SSN oe 


F 


A ‘  S- 
4 ¢ 

A 

a vetav?d 

| 7. 


Not 2 tkeati 


REEFS. 


THE HELIOTYPE PRINTING CO,, BOSTON 


ns 


179" 


LAKEMBA 


5 MILES 


Soundings in fathoms. 


ONEATA PASSAGE 


Uekalel 
eka 
ed 


Pr.21. 


Bi 


j 


Soundings in fathoms. 


een wey.) oa , . } hs as i) 7 


DS AND CORAL REEFS. ; Pr. 22. 


i 1% 
water 
35 /Thakau Vau 
7 
360 
a0 
150 
160 
oN AMUKA (250) 
PEP \danacly wooded! 
Vv 


Soundings in fathoms. 


FULANGA 7 


THE HELIOTYPE — 


470 ft 
16 


ae i Level = Seam bevet 

16 g 

Kambara 
Fulanga Adolphus Reet 
ie W. E 
100 100) , 
asoft zofl 4. zeoft 6 Zoot 
isoft 17. 
Pee Level a» Sea Level 


10 


Ongea Levu 


Ww a c nef 
Ores E Adolphus Reef 
NW SE 


100 


Sea Level _ Level 


Levu 


Ongea 


a 


wutuiloma 
On gea N 


too Nuku Mbasanga 


zioft ago ft 
100 


Sea Level 


Sea Level 


Pie 1s 7 
Navutuira 


a 0 
Yangasa Levu 


‘Oneata NW 


E Yangasa 
100 
Joo ft oft 
5 Loa ie 
zo To 
Oneata jE OLE LO SSE ‘ 
Soundings in fathoms 
BE Nw Heights in feet sno ft 14. 
Sea Level 
13. 200 ft = ; 
Sea Level 
™ = 
$s 
Oneata 100 
N. 
100 100 


B Meisel hth Bstes 


j 


S * 
> 
: 
5. 
gos, Jew tial hey 
Seer Lo Le uae \ 
P A ie i un 1 at 
tat) 


Pula ees 


a ay es, We 
( (pe) 
4 war b 


‘ Lt Oe A 
© a Wwe Me 


Oude e 


F odomnane pats ae 35 


wn 4 


pf wadeemo 
4 * 


girotitesaiet 
» winpaat 


¢ ica f pat Ly ry Lae Fi 
ie ee ? " Py basil ‘nA yA iy 1 we 


Séa Level 


3 


Wakayva 


PLATE 22> 


2 fr aT 5. 
a6 ft 
go4 ft 4 
- N f Ngele Levu’, 
Sea Level if F f 
Sw eS = 
J D 19 
Nairai E Makongai 


Sea Level 


Yanutha 


Lomaloma 


pal Vatu 
bullia 100 ‘ 100 
’ ‘S 
Te i ¥ 
Great Astrolabe Reef N 
100 
~ y Sea Leve t 
Bry En 
32 + 
Vanua Mbalayu 
hi00 Soundings in fathoms. 
Heights in fect. 

’ BMetsel lth Bast 


a 
2). 
‘A 


ee, wag CI 


= { 
‘e2kon cat wr 
a ey a i : 
wat 
&. 


hide £1 fe 


F f} one 
Hoos 2 
§ — 
” % 
/ fs 7 
4 iP YS“ or OD 
ae \ (44 Lb # 
Tod ; alk 
a * at ) ~ 
gn) } ‘ {* 


ol 
. ; ia Awa »! 
~ . j 2 


ae 
ax 
a ae 5 oe ee 


ee at se Ss =e 
oF j 1s ar, a pe 
. + re Reale Mod tow ‘Ne 


rvyatiadM mural 


48 te pir 


Jo le 


Pi 


Wet op 
raoltzen 


TOTOYA 
SOUNDINGS IN FATHOMS 
HEIGHTS IN FEET 


——— 
1 MILE. 


PLATE. 234 


Sea Level a 


PENGUIN BANK 
13 


Impounded 


peVUATA deep water 


be, Ra 
UM. 
€ 


Set 
5 Tae LEV 


A cont 
aslo 


Q HORSE SHOE REFF 


Jz 


THAKAU MOMO 


THAKAU- MOL. 


Soundings in fathoms. 


Meisel bth Bouse 
Heights in feet é 


oO 


Witcee, 


LA 
* 
s¥ 
se 
Z ; 
a 
os 


449R J0He A2HOKe 3 


OMOM UA HART SS ov 
*S.™ en ee 


is “ me ins 
key PHA KA tees 4 
é ov . % = + 
. hr > \ br aa ia 


A *N LOVASHTIG “8 ‘9dALOLNY 


he iw ley _ sjaay [e1og pur spurysy ifty,, 


_ 


‘AVG WIVHLOVT SSOYHOV “SAERYN YAINYVE 


“ACN ‘LOVISH3IG "3 ‘SdA1OLYY 


OR 


~se Feng SIE 


. SJody [e1OD pur spuryjsy ft 


eee Dd 


‘VANS OL SONVYLNS dO aqais LsaM ‘LV1d AAA 


‘9% ALVIG .SJO2Y_ [e10D puv spurjsy lta,, 


WANS OL FONVYLNA JO ACIS LSAM ‘LWIA AAaY 


ACN 'LOVISHRIB °39 ‘SdALOLHY 


‘Le ALVIg . SJoay [e10D pur spurjsy ifty,, 


> 1 


‘VANS OL FONVYLNA dO ACIS LSVA “‘LVIA WHOdOTIIOOd 


‘A "N ‘LOVISHSIG °3S "3dALOLYY 


O10Hd WOR 


"QZ ALVIg , Joey [e10g pur spurysy ifty,, 


HAONVULNG VANS HO ACIS LSVH LVIa VdOdOTTood 


‘62 ALVId . SJ2ay [e10oDd pur spuryjsy tfry,, 


“‘VULAWONIHOA AG ONGC STANNVHO 


AUN ‘LOVIGN9IG “3 ‘IdALOLYY IL0Kd “HLNOMO 


‘of ALVIg _ $Je2y [e10g pur spurysy ify, 


PEATE: 37: 


“Fiji Islands and Coral Reefs.” 


PHOTO 


A., 


ELEVATED LIMESTONI 


VANS HO HOSUYVH YANNI LAISI ANOLSHWIT GAALVATS 


NOLSO08 “OD ONLANIMd IdALONISH JHL 


.- ue spurjsy ity ,, 
‘22 ALWId . SJaay [RIOD Pp pues] |! 


. 
ini @ 


‘LSVA AHL WOYd NVWIVAO 


A'N ‘LOWAGHRIG "3 '3dALOLN 
: eS ee 


Pe tig RE 5 
l See ae aie 
i as ane 2 ey 


‘SS aes 


.. 8J90qY [e10D pur spurysy rfry,, 


ie ke ttn 


‘LSVH GHL WOdd VANAUT 


A °N ‘LOVAGHGIG ‘3 ‘Sd 0 


lah 
© 
7 
“ 


PSs ae . SJ29Y_ [VLD pur spueysy ifty,, 


7 a 


‘ACN ‘LOVASHEIG °3 ‘3dALOluY 


Ge aLWviIg 
en 


‘OVEN WOU LSHM HLAOS ONIMOOT SLVYIT4 


OLOKd '* 'WOn Mm 


« SJoayY [e10g pur spurysy rf1,7,, 


NOLSOB "OD ONILNINd AdALONIISN ahd 


—— 
te 


en ee 


3 


pee = 


‘SUYALV AA 


NVAW AUNV'ISI 


VMIA 


«$224 [IO pue spurjsy ity ,, 


“LSVG FHL WOU NAS ‘AAAY IV TISVN 


A 'N ‘LOVISH3IG ‘3 "3dALOULYY OLOHKd M WOW 'M 


‘LE aLvig | ) . 8J22y STes0g pue spurysy ity, 


‘SSANW ISI VAN'TIVHOW AUNV AVINYON 


‘ACN ‘SOVIGURIG "3 ‘FdALOLHY 


OLOHe ‘WHinOMO00OM 


a ie ore or | 


‘gf aLvig .. 8J29Y [e10G pur spurjsy ifry,, 


ate 


CGANW ISI] NVWINMNAN HO AYOHS HLYON 


sa 


‘OL ALVIg « Seay [e10D pure spurysy iftyy,, 


NOASOH “OD ONILANINd ¥dALON 


‘oF ALVIg 


« §J92Y [VIO pue spuejsy uty ,, 


PLATE 41. 


“Fiji Islands and Coral Reefs.”’ 


ISLAND FLAT 


NUBRULAU 


a, 


NAAT OWOM AHO OLYIA ARRAY ONIONIYS 


NOLSO8 “OD ONIANING FdALONIIN Jha 


‘tb ALVIg « SJ292Y [e10D pue spurysy ifyyz,, 


MAAIM WHOLVYDNIS FAO HLNOS Asad DONIONIS 


A) A SHSIG “9 3dALOLYY 


EP Ey te _ SJaoy [e109 pur spurjsy ifty,, 


"HSATEH VHOLVONIS: dO HLYON SENNA AUNYS 


"ACN “LOVASHSIG "9 '3dALOLNY OL0n4d "Vv 'W 


~ 


~ 
pee 
price 
nee 


PY. Shy ty _ SJoay [e1og pur spurysy fy,, 
-_ _ 4 wag ee el ee ee . fs otra — pein GP Sea e ; <) — 


NOLSOB OO DNILNIMd AdALONIIM aNd 


ee ee a 


‘St aLVIg « SJooy [Vlog pue spurysy ity ,, 


“Fiji Islands and Coral Reefs.” PLATE 46. 


MAX AGASSIZ, PHOTO 


AAOTad GAOHsS 


4 LNOMO00M 


N ‘LOViSHSIG ‘De 'SdALOLYY 


Del! 
bi mae 


ee 


2 ~ 


” 


_Sfaay [e1og pure spurysy tly 


‘AVG IMIYNLOW WOUA NAYS VHONAAW 


"ACN ‘LOVISNSIG “3 '3dALOLYY OL0HKd ‘*Y “W 


‘gh aiv1g . 89Y [eID pue spurjsy ilt,, 


‘ANVW'ISI WHOLS HO LNIOd bt 


xX 
bu 
i 
(~ 
r4 
+L 


AN ‘LOVIONDIG “9 ‘AdALOLSY OLOMd ‘WisOmMC00M 


Ya 


‘6b ALV Ig . SJoay [e109g pure spurysy ify, 


‘NAVGNV™M SHANITdA AW ISHA NHOP 


OLOnd ‘ZistwOyv HVA 


NOLSOB (OO ONIANING AdALOIIAH JHL 


‘oS aALWIg . SJ29y [e10D pur spursy ily ,, 


NOODWT AHHH AEAVIOULSV LVAHYD ANVISI ONO ACIS LSAAAHLYON 


NOLSO8 "OD ONILNINd BdALONISH FHS ‘ 
10d ‘7 Y xn 


‘28: Abad . SJo9y [e10D pure spurysy tfiy7,, 


NOOOVWT HHee BAVIOULSVY LVAHO IV! IVT BANANVA 


‘28. cee « SJaay [e10og pue spurjsy ily,, 


‘NOOOV' ARHY AAVIOULSVY HLYON ‘ASNOH-LHDIT YOOU O10S 


NOLSO® (OD ONIANING TAA LOIIIH Bod 


OLOned ‘TitewOW xR 


« SJ92Y [eIOD pue spurysy ilty,, 


‘NOODOVI dAaaY AGVIOULSY HLYON MOOd O'lO' 


AN ‘LOWIGHSIG 9 'IdALOLUY 


‘bS ALVIq _SJaay [e10g pur spurysy ity, 


‘ANVISI VAVHYVM JO AOVA LSAM 


"A "N JOVISHSIG "3 "3dALOLYY 


Sie. seas ,SJeey [vlog pure spurysy ifty,, 


‘NOOOV'T VAVYVM OLNI dOVSSVd HO ACIS HLNOS 


‘ACN “LOVLSNRIB °S “FdALOLUY 


OLOWd ‘HiNOMOOOMm 


. SJ92qY [e1OD pure spuryjsy ify, 


f 


‘VWIVOW AO ACIS LSVa 


‘ACN ‘LOVLIGNDIG ‘a ‘9dALOLUY OLOHd 'HiNOMO0OMm 


jooy [v10d puv spurysy ifty,, 


IVdIVN 4O FdIs LsaM HALAOS 


“A *N LOVISYHRIG ‘3 ‘3IdALOLNY 


°9S aALW'Ig _, S$Jaay [vsog pure spurysy ifty,, 


“MOODVT I[VHIVN “GNVISI NAO 


a 
"ATN LOWLGUMIG “3 “AdALG LEY OLOWd “HiwOmMooOm 


Of ELV Ig _SJaey [e1or) pue spurysy ify,, 


eke 


oar 


‘INOIAVL SO LNIOd HLYON JAHO SLOATISI 


"A "N LOVIGHSI@ 9 “SdALOLNY 


O10na “WY 


‘09 ALY ., 8JeyY [e10D pur spurysy ifty,, 


‘SSANVTISI O@WOdWIy 


"ACN ‘AOVAGNRIG “3 ‘3dALOLUY OLOHd ‘HinOMO0OMm 


"tO ALVIS _ SJeey [e10D pue spurysy if1y,, 


‘AVI ‘AYOHS GaAdONT 


"A "N LOVISHSIG "9 *IdALOLNY 


OLOnWd 'GBNOF *O “8 


‘29 ALVIg .SJ2Y Te1OD pur spurjsy rf, 


NOLSO8 OD ONILNINd 


"£9 aLVIg 


MALO! 


13H BHA 


( 


) 


LNIOd 


- 


LSVAHLYON 


i aa 


.SJ99Y [eIOD pur spurysy ity, 


OWON AO SYOHS HLYON ‘HOVAd 


oy yf A 
ACN ‘AOVLGNRI8 "3 '3dALOLUY OLOHd ‘HiWOMCOOm 


‘VQ ALVId _$}Jaey [eIOD pur spurysy ifty,, 


‘ONOM LVTA VeOdOTTIOOd 


A 'N LOViSeAI 2 adALOLUY 


Cg ALV'Id _ sjaay [e10d pur spurysy ifty,, 


& 


“SSOWHILSI SHL SSOWOV NAS “VAOLOL JO WI LSVa 


‘99 ALVIg . SJ29Y [eIOD pure spurysy rf, 


‘NISVG@ YALVYO VAOLOL OLNI DONINAdO 


NO1SO8 “OO ONILNINd BdALONVIH SHA 


OL0ne4 ‘ZiG8VOW KYA 


£ or Naas 
Deane a Sen bal 


‘Lg aLlvig . SJaey [e1og pur spurysy ify,, 


‘LATING WOH VAOLOL JO YALVYO OLNI DONIMOO'T 


NOLSO0@ OD ONIANINd BAALONNSH BHA 


OLOKd 'ZiSSVOW xVA 


"89 avid | «3J92Y [PIO pue spurysy ify ,, 


NOLSO8 (OS ONIANIMd IdALOIIIM BHL 


69 ALVIG 


NISVa GUPLVYD VAOLOL 


HO 


WI 


LSVHHLYON 


OLOne ‘ZitbwOY THA 


«¢ $29Y [POD pue spurysy if, 


VIAWOHL HO NISVd daLveo JO Wid Gadods 


ACN ‘LOWLIGNBIG ‘ar ‘SdALOLYY OLOHd ‘HiNOMO0 OW 


OL SL 'tF _, Sf9ay [es1oy pur spurysy ify, 


VIVAVATVH AO YALVHO 


“ACN “LOVIGNZIG “9 ‘SdALOLNY 


« 
+3. 


Sia aS el : 4 “ 
A’ ee ae SS : - ee | 


«8J22Y [P10 pure spurjsy ifty,, 


‘12 ALVIg 


‘NOODV1 JO ACISNI NAVIVEN VONVA JO ACIS LSVA HLYON 


A *N ‘LOVISUSIO “3 “SdALOLYV 


gf a _ SJaey fe1og pure spuryjsy ifty,, 


GQNVW ISI] HVTIIONVTTIION JO LNIOd LSVH HLYON 


AN ‘JOVISH3IG ‘9 


OL0Hd 'HINOMOOOW 


oa 


er. Ia 
A ae 
_ ramet y _ 


one 


‘CL Divi . $J29y [e10D pur spurysy rfiyq,, 


PLATE 74, 


“Fiji Islands and Coral Reefs’ 


Y 


€. BIERSTAOT, N. 


ARTOTYPE. 


WOODWORTH PHOTO 


ISLAND. 


SHORE OF NGILLANGILLAH 


EAST 


CANON, 


% 


"NOOOVT OAWIVEW VONVA CANVTISI VAAV 


“A 'N ‘JOVISURIG “a ‘SdALOLNY 
— O10Md "HINOMOOOM 


OL Sa wig 
, SJoay [e10D pure spurysy ifr, 


GIN Vish EY TIS Sy TION, <b te IND 


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« S$J99Y «[e10D pure spurysy ifiy,, 


‘OL aALVIg 


VAVENVS HOVaea OVIvVaA0oL HO Aiton Senta ANGST 


AN ‘JOViSNRIG 2 


‘hh Givig 
.SJ29yY [V1OD pur spurysy ify, 


‘VUVENVA ‘AVIOMOL AO HLONOS “TITIH OINVOTOA 


*gl ALW'Ig _ SJoay [e1og pure spurysy ifty,, 


VHUVENVN HO AYOHS 


| 
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= ~ oat = 


OL ALVIg 


Sjoay [10D pur spurs] ify,, 


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VONVINA JO ACIS LSVAHLOOS 


AN ‘LOVLONBIG 9 3UALOLUY 


O40m4 ‘HAN OMU00M 


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08 ALVIg ‘S ' 
« SJOPY [P4OD puv spueysy eft 7,, 


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NOLSO8 ‘OD ONILNIMd AdALOIIAH BL 


asd 
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‘1g ALVIg < SJ99Y [eIoD pur spurysy ify,, 


‘ANNOS GNV NOODWT VONVTNI OLNI FZONVYLNG 


AN ‘LOVISHRI8 “3 ‘SdALOLUY 


OLOHd ‘HINOMGOOM 


—————— 


‘29 ALVIg «. SJO9Y [BIOD pur spurysy ifty,, 


‘ANNOS WONVINA NI SLATSI 


A °N ‘LOVISHOIG 7 “9GALOLYV 


‘€g ALVIg _(s}aay e1og pue spurysy ity, 


A 


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‘JOVIGH3IE ‘3 'adALOLUY 


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‘ANNOS 


VONV INA NI 


SLY ISI 


ce DFPA A [e10o,) pue spue|s]y i(1,7,, 


‘OONWW JO LSVOO LSVS3 HLYON ‘d¥9 MOT 


OLOHG 'HiINOMCOOM 


“SQ ALVaAg _, SJaay [e109 pur spurysy fy, 


‘TOONVW HO LSVOO LSVa SdANTA ANOLSHNIT CALVAGTS 


A *N ‘LOVISHSIG 1 “IGALOLYY 010K HiNOMO00M 


"OO Biwi _ Sjaey [e109 pur spurysy ifty,, 


OONVW JO ACIS LSAM HLNOS NO SLAISI OINVOIOA 


“AN ‘JOVIGHRIS "3 ‘3dALOLNY 


OLOWd 'HiNOMO00M 


Lg aLvig .SJOaY [e1OD pur spurjsy ifry,, 


VHLOANL AO LNIOd LSHMHLYON 


AN ‘LOWLSHBIO 9 ‘SdALOLHY 


"OLOMed “HiNOMO00m 


hag ope te ae = 
a cnceieihidiemeiaeie Ea ae Sai a ranararcenced 


"88 ELVIg .8J22Y [e1OD pur spurjsy ilty,, 


VHLOANL AO LNIOd LSVAHLAOS 


"ACN ‘LOVAGUIIG “BS 'IdALOLHY OLOHKd 'HinOMGOOm 


eh nage ne a 


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ACN ‘LOWASHSIG §3 ‘3dALOLHY 


VSVONVA ACISNI 


“LSVAHLAOS 


AA 


WOH 


VHLOAVA 


"OLOKS ‘Hiwomaoom 


« SJOOY [PIOD pue spuryjsy rfty,, 


“VSVONVA ‘VWNOTINLAAYN JO ACIS HLYON NO AVA 


A'N ‘LOVLSHSIG ‘3 '3dALOLYY 


“Speoy [elo pur Spurjsy fy, 


‘VSVONVA VNOTINLOAVN HO AYOHS HLYON NO LNIOd 


NOLSOB “OOD ONILNINd FdALOI IIH 


w 


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‘VYSVONVA VAWOTIN.LOAAVYVN HO AVG NI .LAISI 


NOLSO@ O95 ONIANIAd FdALOININ and 


OLOnd ‘ZievOV KYA 


= 
ne 
——— 
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— 
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"£6 ALVIg « SJ9ay [RIOD pue spurysy ity ,, 


IMIYMQN VHONO HO AYOHS 


NOASOB OD ONILNINd AdALONISH JHE 


H LYON 


a ea ete = en a 
Se 

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NOODVT NAWT ATAON \LAISI VITWINVL 


40nd ‘ZIOGVOW KA 
NOLSO8 09 ONILNINd 3dALOIISH ani 


"$6 aLVIg 


«SJ29Y [RIOD pure spurysy tfy,, 


NOOSVYT OAT SISSON CGN Is! 


‘90 ALVIdg .SJeay je1og pure spurysy ify ,, 


‘NAAT HIGON JO LUYVd TIVYLNdo 


“. NE “3° 
A "N ‘LOVIGNSIG “3S “SdALOLUY @1L0Kd HiNOMG00M 


"£6. ILW 1g _ SJaay [e1oD pure spurysy ify,, 


GNVISl DAT BaeoON HO Hoy 


NOASOB 'OO ONILNINd FdALOIIIM AHL 


“Fiji Islands and Coral Reefs.’’ 


2 


\' 


VEGETATION, WEST SHORE OF NGEI 


AUAT ALVA JO AYOHS LSAaM HLYON “dn 1d 


‘OLOKd "VY OW 


‘OOl ALVIg _ sJaay [e1og pur spurjsy ifty,, 


‘NOOOV'T ATIAT ALVA ‘SLAISI NAVS ALVA 


NOLSO8 OD ONILNIMd AdALOIIIH AN OLOMed ‘ZievOW KYA 


—— — 


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AON ‘LOVLSuaI8 "3 ‘AdALOLUY 


OLOHd 'HLNOMOOOM 


‘ZOl ALVIg » _ syaay erod pur spurysy ifty,, 


NAAT QOYNNVN JO NYOH NYSAHLNOS 


ACN ‘LOVLISHSIB "3 ‘3dALOLHY 


O1°%Hd “HiNOMO00m 


Ol Luvig « SJooy [e10D pur spurysy rif17,, 


NOASOH 'OO ONILNINd AdALONAK HL 


POR Sivi14 


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SfooyY [eIOD pure spurs] iy,, 


‘QATTL OVOANVN TO LV ld Agae Nese oos 


"A 'N LOVAGHSIA "3 “FGALOLNY 


“fOr Zivig _spaay [eiog pur spurysy ify, 


‘NAAT OMONVN AO AYOHS LV NO 


"AN ‘LOWIGH3IS “3 “3dALOLNY OLOHd ‘Hi NOMOOON 


‘901 ALVIg . SJ90y Te10oD pure spueysy rf1y,, 


OO ———— | 


‘ANVISI IV1 IV1 OMANVWN HO NOILISOd ONIAMNOOO ‘SAVEHH OXON 


NOLSO8 ‘OO ONIANIMd BdALONIAW AHL OL0ne ‘ZistvoOV xvA 


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‘VONVSVEW OMON OUNV GALWIVEN NYAON 


‘OLOHd “M "WOW 


"AN ‘LOWLSUHSIG "3 IdALOLYV 


"201 ALV'Id _, SJ2ey [e10D pue spurysy ify, 


NOLSOB “OO ONILNINd AdALONIAH AHL 


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‘WIVTIONV TIA M 


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NYa.LSa AA 


OLOMd ‘7186VO"¥ ¥¥R 


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‘ANVISI WIVWIIONVIGAM JO LNIOd LSVAHLYON 


LOVLGURIG “3 


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¥ 


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"A 'N ‘LOVISHSIG "3 'IdALOLYY 


FUT WL id 


‘VMAIVYAT AVYVHL JO NYOH LSvd HLNOS 


OLOKd HLNOMO0OM 


, $J2aW [e10D pur spueysy Wl, 


IVI IVI VNLOW HO NHYOH LSVAHHLYON 


OLOMed “2iSSVOW FA 


NOASO@8 OD DNIANINd BdALONISH and 


tir Soll Space 
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‘ZI ALVIg  S$99y [RIOD | pues] ty», 


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a WA ahha n)y ratty Paced Te. 


mORINMEINGA SEwWI.MAY 16 1966 


QL Harvard University. Museum 
1 of Comparative Zoology 
H3 Bulletin 
VeS2—33 wat 
Biological qb 
& Medical Xb 
Serials 


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