Reports

•&•

v.8
pt.H

REPORT

OF THE

CANADIAN ARCTIC EXPEDITION

1913-18

VOLUME VIII; MOLLUSKS, ECHINODERMS,
COELENTERATES, ETC.

PART H: MEDUSAE AND CTENOPHORA

By HENRY B. BIGELOW

SOUTHERN PARTY, 1

OTTAWA

THOMAS MULVEY

PRINTER TO THE KING'S MOST EXCELLENT MAJESTY
1920

Issued June 30, 1920.

Report of the Canadian Arctic Expedition,

1913-18.

VOLUME VIII: MOLLUSKS, ECHINODERMS, COELENTERATES,

ETC.

Part A: MOLLUSKS, RECENT AND PLEISTOCENE. By Wm. H. Dall

(Issued September 24, 1919).

Part B: CEPHALOPODA AND PTEROPODA. By S. S. Berry and W. F. Clapp

i (In preparation).

Part C : ECHINODERMS. By Austin H. Clark (Issued April 6, 1920) .

Part D: BRYOZOA. By R. C. Osburn (In preparation).

Part E: ROTATORIA. By H. K. Barring (In preparation).

Part F: CHAETOGNATHA. By A. G. Huntsman (In preparation).

Part G: ACTINOZOA AND ALCYONARIA. By A. E. Verrill. (In preparation).

Part H: MEDUSAE AND CTENOPHORA. By H. B. Bigelow (In press),

Part I: HYDROIDS. By McLean Fraser (In preparation),

Part J: PORIFERA.

REPORT

OF THE

CANADIAN ARCTIC EXPEDITION

1913-18

VOLUME VIII: MOLLUSKS, ECHINODERMS,
COELENTERATES, ETC.

PART H: MEDUSA AND CTENOPHORA

By HENRY B. BIGELOW

SOUTHERN PARTY, 1913-1916

OTTAWA

THOMAS MULVEY

PRINTER TO THE KING'S MOST EXCELLENT MAJESTY
1920

Issued June 30, 1920.

Medusae and Ctenophores from the Canadian Arctic
Expedition, 1913-18.

By H. B. BIGELOW

Museum of Comparative Zoology, Cambridge, Mass.

The medusae and ctenophores described in the following pages were col-
lected by Mr. Frits Johansen, in shallow water at various localities along the
Alaskan coast, and the arctic coast of North America, between June, 1913, and
August, 1916.

The material, in formalin, is in part excellently preserved, but in part so
fragmentary as to preclude satisfactory identification. As might be expected
of any collection of Medusae from the Arctic littoral, it consists for the most
part of well known and widely distributed arctic species. But it includes one
new Anthomedusa, the representives of which are, fortunately, in an excellent
state of preservation (p. 7n).

To give an idea of the difficulties under which Mr. Johansen worked, and
the credit due him for making the collection at all, I can do no better than quote
his own words, from the field notes submitted to me: —

" The difficulties under which I collected Medusae and Ctenophora during the Canadian
Arctic Expedition were great. The opportunities for pelagic collecting were exceedingly few
and these had to be devoted to trawlings, etc. Best results were gained by working from the
fall ice in bays; but the temperature of the air, at this season, made the water freeze quickly
in the specimen jars, so often the Coelenterata collected were spoiled before I could reach the
house. The storing and the caring for the specimens collected during the three years hi the
Arctic was also trying ... as formalin specimens froze . . . and they thus represent
only a part of the Coelenterata actually observed, collected, and preserved."

LIST OF SPECIES.
ANTHOMEDUSA

PAGE

Sarsia princeps (Haeckel) 4n

Sarsia flammea Linko 4n

Bougainvillea brittanica Forbes SH

Rathkea blumenbachii (Rathke) 6H

Halitholus cirratus Hartlaub 6n

Eumedusa similis, gen. et sp. nov 7n

TRACHOMEDUS.E

Eperetmus typus Bigelow 9n

Aglantha digitate (Fabricius) 10n

NARCOMEDUS.E
Aeginopsis laurentii Brandt HH

SCYPHOMEDUS^E

Halidystus stejnegeri Kishinouye 12n

Chrysaora sp. (?) 13n

Cyanea capillata (Linne") 13n

Aurelia limbata Brandt 14n

CTENOPHORA

Mertensia ovum (Fabricius) 15n

Beroe cucumis Fabricius 1 5n

Bolinopsis sp. (?) 15u

4n Canadian Arctic Expedition, 1913-18

CRASPEDOTjE.
ANTHOMEDUS^E.
Family CODONID^

Sarsia princeps (Haeckel).

PI. I, Fig. l.
Codonium princeps Haeckel, 1879, p. 13, pi. 1, fig. 3. For synonymy, see Mayer, 1910, p. <><).

Eleven species of this large, easily recognized, and characteristically arctic
species were taken at Collinson point, Arctic Alaska, from September 19 to
October 14, 1913 (stations 27m, 27n, 27r, 286), below the sea ice, which had
already formed, by that season, to a thickness of 8-10 inches, the temperature
of the water, below the ice, 29°-30° F. Also one excellent specimen, about
18 mm. high, from cape Smyth, point Barrow, Alaska, station 57a, August 8, 1916.

Except for the geographical records, discussed below (p. 16n), these excellent
specimens, ranging in height from 11-19 mm., add nothing to the previous
accounts of this species (Haeckel, 1879, Bigelow, 19096). A figure of their general
appearance is given, however, to aid students of the Arctic Medusae in identifi-
cation. And it is worth noting that in this species, as in S. mirabilis, the man-
ubrium is extremely extensible (PI. I, fig. 1). For, as Mr. Johansen states in
his field notes, it "can protrude its long, slender stomach to three times the
body length, the four tentacles to five times the body length."

Briefly capitulated, the characteristics of the species are its large size,
long, slender manubrium, the jagged margin of the narrow radial canals, the
distinct basal tentacular bulbs, usually (but apparently not always) with con-
spicuous ocelli on their outer faces ; and especially the well-developed apical
canal, projecting, aborally, into the substance of the bell, from the point of
junction of the four radial canals with the base of the manubrium.

Of these characters the most variable (except for the length of the manu-
brium, which is largely dependent on the state of contraction of the specimen)
is the waviness of the margins of the canals. Something of this sort is usually
to be seen. But in the present series there are various gradations, independent of
the size of the specimens in question, from canals distinctly toothed and jagged
to others but slightly wavy. And it is not unlikely that specimens may occur
in which their margins are perfectly smooth.

Colour: The value of the series is much enhanced by a beautiful coloured
drawing of a specimen from station 27r by Mr. Frits Johansen, naturalist on
the expedition, which shows the entodermal core of the manubrium of a violet
tint, radial canals and tentacles pale pink, and the ocelli carmine.

Sarsia flammea Linko.

Plate II, Fig. 5.
Sarsia flammea Linko, 1905; p. 212. For synonymy, see Hartlaub, 1907, p. 12.

Two specimens, about 19 mm. high, Collinson point, stations 27r and 286,
October 2 and 14, 1913, when Mr. Johansen notes the species as common
under the sea-ice. Two specimens, about 8 mm. high, station 57a, Cape Smyth,
point Barrow, Alaska, August 8, 1916.

The most characteristic feature of this species, a negative one, is the absence
of ocelli. And this, coupled with its short manubrium, short, stout tentacles
with large basal bulbs, absence of apical canal, and large size, make it easy to
recognize. The present series adds nothing to the good account by Hartlaub
,1907), with which they closely agree.

Medusce and Ctenophora 5n

A colour sketch, taken from life by Mr. Johansen (station 27r) shows
manubrium and tentacle bulbs reddish orange, which agrees with the earlier
accounts (Mayer, 1910, p. 64), the tentacles themselves pale bluish.

Sarsia flammea has previously been recorded from various localities in
Spitzbergen, from Greenland (Hartlaub, 1907), and from Barents sea (Linko,
19Q5).

The species is so closely allied to S. japponica (Maas, 1909, Bigelow, 1913)
that it may finally be nceessary to unite them. The only character which has
been invoked to separate them (japponica like flammea lacks ocelli) is the fact
that in the specimens of japponica so far examined by Maas and by me (1913)
the sexual products are irregularly massed, while in flammea they occupy the
whole gastric wall except for its proximal and distal extremities. But inasmuch
as the specimens of japponica which I have seen (1913, p. 4) were not in the best
of condition, the question may be left open for the present. .

Family BOUGAINVILLEID^E Gegenbaur.

? Bougainvillea britannica (Forbes)

Hippocrene britanica Forbes, 1848, p. 84, fig. 2. For synonymy, see Mayer. 1910, p. 161:
Hartlaub, 1911, p. 162.

Station 66; lat. 56° 26' N., long. 133° W. (off southern Alaska); June 24,
1913, surface, 1 specimen, 6jmm. high, in formalin, in fragmentary condition;
also coloured sketch of same, from life, by Mr. Johansen.

Our knowledge of the Medusae of this genus from the Pacific coast of
America is so scanty that it is much to be regretted that the collection contains
only a single specimen, and that one in such poor condition that it can only be
provisionally identified. Its large number of marginal tentacles (27 in one
bundle) class it with either B. brittanica, B. principis, B. bougainvillei, B. mac-
loviana, or B. super ciliaris. But as it has no trace of peduncle, it cannot be
associated with either of the last three. As between britannica and principis,
it is best referred to britanica, for the following reasons.

Although apparently sexually mature (to judge from the large gonads), the
labial tentacles branch at most four times, as is usually the case in britanica
(Hartlaub, 1911, p. 163), whereas in principis, according to Hartlaub (1911,
p. 177) they are much more complex. The gelatinous substance is not especially
thick: there are about as many marginal tentacles as in britannica; the small
axial ocelli are similarly situated on the bases of the free tentacles; and the
marginal tentacular pads are shorter than the spaces between them, whereas
in principis they are longer. On the other hand, in their rather linear outlines
they more nearly approach principis; and this is also true of the short-stalked
condition of the labial tentacles. The gonads, so far as can be seen in their
present state, are adradial, which is true of both britannica and principis.

In colour, this specimen agrees fairly well with britannica, its manubrium,
as sketched by Mr. Johansen, being dark reddish brown, tentacular pads grey,
ocelli black.

In britannica the gonads are described by Hartlaub (1911) as brown with
reddish tint; the manubrium having a yellow stripe in each interradius. Ac-
cording to Forbes (1848) the manubrium is reddish orange, while Mayer (1910)
describes the endoderm of the stomach as golden yellow.

Considering how many collections of Medusae have now been made along the
northwest coast of America, and in Bering sea, it is surprising that the Medusae
of Bougainvillea have so seldom been taken or described thence. So far as
I can learn, the complete list of records is as follows : — B. bougainvillei, probably
identical with B. superciliaris (1913, p. 9), by Mertens in Bering sea in 1829,
many specimens (Brandt, 1838). Probably identical with it is the B. mertensii of

63246—2

6n Canadian Arctic Expedition, 1913-18

L. Agassiz and A. Agassiz (1865), common in the gulf of Georgia; but of this
no full description or figure has ever been published, nor is it sure that the
hydroid described as mertensii by A. Agassiz (1865) and by Fraser (1914) belongs
to the Medusa in question. Finally a Bougainvillea from Victoria harbour,
British Columbia, has been recorded by Murbach and Shearer (1903) as B.
mertensii, which apparently belongs to superciliaris. Torrey (1904, p. 7), has
described the hydroid stage of a new Bougainvillea, B. glorietta, from San Diego,
California, but its free Medusa is still unknown. And my own account of a
typical B. superciliaris from Attu island, Aleutian islands (1913, p. 9) completes
the list.

Considering how wide an area is covered by these few records, and how
many species or races of Bougainvillea are known from both sides of the North
Atlantic, probably the present record of B. britannica is but a forerunner of
others to come from the Pacific.

B. britannica was previously known from both sides of the North Atlantic
(Mayer, 1910; Hartlaub, 1911), B. principis from North European waters and
from Barents sea (Hartlaub, 1911).

Rathkea blumenbachii (Rathke).

Oceania blumenbachii Rathke, 1835, p. 321. For synonymy, see Mayer, 1910, p. 177, 179,
and Hartlaub, 1911, p. 229.

Stations 25 b, c. Arctic ocean, off Cooper island, near point Barrow, Alaska,
August 27-28, 1913, eleven very fragmentary specimens. Station 18d, lat.
62°N., long. 167° 30'W; July 7, 1913, one specimen, 2mm. high, in fair condition.

The number (8) of marginal tentacle-bundles and the structure of the lip
and oral appendages make identity with the larger series from New England,
Newfoundland, and Bering sea, with which I have been able to compare them,
certain (19096, 1913). All the specimens show budding phases; but they are
in such poor condition that they add nothing to the numerous existing accounts
and figures of this well-known species.

From its wide distribution in Arctic waters, this species was to be expected
off the northern coast of Alaska (1913, p. 11).

Family PANDEID^E Haeckel.

Halitholus cirratus Hartlaub.

PL 1, Figs. 2, 3.
Halitholus cirratus Hartlaub, 1913, p. 274. .

This species has several times been recorded from arctic waters, as " Tiara
conifer a Haeckel." But Hartlaub, who has seen the original specimen of coni-
fera (1913, p. 284), found that it was really probably a Catablema vesicaria.
Therefore to the specimens recently recorded as conifera and to others he him-
self has studied, he has given the name Halitholus cirratus.

The species has been fully described by him, and he has given in detail
the grounds for considering Halitholus a genus distinct from other Pandeids,
chief of these being the combination of gonads of the Leuckartiara type, with
folded lip, and lack of mesenteries; the latter separating it from its closest
relatives, Leuckartiara and Catablema. So far, two species have been described,
both by Hartlaub (1913), H. pauper and H. cirratus (both had previously
masqueraded as Tiara conifera)', the two separable by absence of peduncle
and few tentacles in the former, its presence, with many tentacles, in the latter.

Medusae and Ctenophora 7n

H . cirratus is represented in the collection by twelve specimens, two in
excellent condition, 13 and 14 mm. high, respectively; the others fragmentary,
from Collinson point, Camden bay, north coast of Alaska, September 15 to
October 14, 1913 (stations 276 to 286), under the sea-ice.

This material adds little, except in the way of confirmation, to Hartlaub's
account of large series. But inasmuch as the species has not been recorded
previously from American waters, a figure and a brief statement of the most
diagnostic features are given here.

The general form of the bell is, itself, characteristic, there being, as Hartlaub
has pointed out, a thick rqunded apical gelatinous projection, with shallow bell
cavity (PI. I, fig. 2), this agreeing with Catablema vesicaria, which Hali-
tholus much resembles in its general appearance, but from which it is easily
separable by such important structural characters as absence of mesenteries
and structure of the, gonads.

In the better preserved specimens there are, respectively, thirty-five and
thirty-six large tentacles, and in each a few rudinentary ones in the various
stages of development.

The shape of the tentacles, with laterally flattened basal bulbs, is much as
described by Hartlaub. All specimens show the low, broad, peduncle, which
is one of the characteristics of this genus, and the four much crenulated lips
(PL I, fig. 3; Hartlaub, 1913). The primarily horseshoe-shaped gonads, with
transverse folds directed toward the perradii (PI. I, fig. 3) recall his figure, as
well as the related genus Leuckartiara (Maas, 1904).

But, while this gonad-type is fundamentally characteristic, the surface
plications of the gonads cannot always be relied on as a systematic character;
for while in one of the specimens it is well exemplified, in the other, an adult
female, the entire interradial zones of the gastric wall are so packed with large
eggs, easily visible even with the hand lens, that the genital folds are obscured.

There are no diverticula from the margins of the canals, either radial or
circular; but the edges of the former are slightly wavy (Hartlaub, 1913).

There are no ocelli.

The only Medusae with which H. cirratus is likely to be confused are
Catablema vesicaria and the species of Leuckartiara and Neoturris. But from
the first of these it is easily distinguished by the lack of mesenteries, by the
smooth- walled canals, and especially by the structure of the gonads; from
Leuckartiara by the absence of mesenteries and ocelli; from Neoturris by lack
of mesenteries and structure of gonads.

H. cirratus has previously been recorded, as listed by Hartlaub,
from various localities in the Baltic, Barents sea and Spitzbergen (for list
of localities see Hartlaub, 1913, p. 274).

The present captures show that it actually has a circumpolar distribution.
But its occurrence as far south as Kiel bay shows that it is not distinctively
arctic in its occurrence, but may be expected as far south as Cape Cod on the
eastern, as well as in Bering sea on the western coast of America.

•Colour: An excellent coloured sketch, from life, by Mr. Frits Johansen, of
the specimen from station 27u, shows the manubrium of a deep pinkish violet,
tentacles pale pink.

Family BYTHOTIARID^ Maas.

Eumedusa similis, gen. nov., sp. nov.
PI. I, Figs. 4, 5; PI. II, Figs. 1, 2.

One specimen, 13 mm. high by 10 mm. broad (type); station 27v, off
Collinson point, Alaska, October 7, 1913; surface temperature, 30° F. ; ice, 10
inches thick. Catalogue No. 26, Victoria Memorial Museum, Ottawa.

63246— 2J

SH Canadian Arctic Expedition, 1913-18

Station 27o: One specimen, contracted, of about the same size, from lagoon
inside Collinson point, Alaska, September 20, 1913; surface temperature, 30° F.;
ice, 5 inches thick. Catalogue No. 3292, Museum of Comparative Zoology.

The type is in excellent condition, fully expanded except for the manubrium
and tentacles. In general out line it is high, bell-shaped, the subumbrella two-
thirds as deep as the bell is high; the gelatinous substance of the bell thick at
apex, thin at sides with smoothly rounded apex and no suggestion of an apical
projection (PL I, fig. 4). The surface of the bell is slightly, wrinkled in the type;
in the other specimen it is furrowed in the radii of the radial canals; but these «
furrows are obviously contraction phenomena.

The most interesting features of this new Medusa are the radial canals and
the tentacles. There are eight radial canals in each specimen, broad and
flat, all arising independently at the center of the apex of the manu-
brium (PL I, fig. 5). The four primary perradial canals are easily
distinguished, by their larger size, from the four of the second -
which alternate with them. But as all are equidistant, there is no evidence
that the latter originate as branches of the former, as occurs in the related
genus Bythotiara. The edges of all the radial canals in the contracted
specimen are smooth, with no traces of lateral spurs or branches, and though
they are slightly wavy in the type, this is apparently the result of muscular
relaxation, at least there are no definite lateral deverticula or spurs. And in
both specimens the edge of the circular canal is smooth, with no trace of even
such rudimentary centripetal spurs as occur occasionally in Heterotiara (Maas,
1905; Bigelow, 1909a, 1913; Hartlaub, 1913).

Tentacles: The tentacles, best illustrated by the type owing to its relaxed
condition, are of two sorts, large and small, arranged as follows: opposite each
canal, and in each inter-radius, is a large tentacle; between these, a varying
number of small ones, of various stages in growth, from mere knobs to fully
developed ones (PL II, fig. 2). In four successive sixteenths of the margin of
the type these number 7, 7, 6, 6. The large tentacles, though agreeing with
the usual Calycopsid tentacle in the presence of terminal nematocyst knobs,
differ from those of Calycopsis, Heterotiara, etc., in being armed with ectodermic
nematocysts, arranged in rings, irregularly scattered, particularly over the
middle third of the tentacle. The large tentacles are, however, strongly con-
tracted, now (in the preserved state) being only 3-5 mm. long; hence, when
expanded, these nematocyst structures probably are less apparent, if visible at
all other than as scattered cells

The large tentacles are hollow (PL II, fig. 1), as usual among Pandeidae and
Bythotiaridse but owing to their contracted state the lumen is very small. Their
relationship to the bell margin is the same here as in Calycopsis, the basal part
of each lying in a groove with the gelatinous substance of the exumbrella pro-
jecting downward between them (PL II, fig. 1). And it is also worth noting that
the marginal nematocyst ring is unusually thick, as compared with that of
related genera.

The small tentacles differ from the large ones not only in size (being about
1.5 mm. long, and apparently not contracted), but also in structure, being
solid instead of hollow, with an endodermic core of large irregular chordate
cells (PL II, fig. 1). But, like the primary tentacles, they too bear terminal
nematocyst knobs, though otherwise without nematocysts. The small tentacles
exhibit every stage of growth, from mere bosses of the marginal ring to fully
formed tentacles, showing that their final number is not attained till a late
stage in growth, if, indeed, new ones are not developed as long as the Medusa
lives. But the largest ones are all of about the same size, and there is no
evidence that they ever develop further. That is to say, so far as the actual evi-
dence goes, it is safe to conclude that there is no intergradation between the twt
classes of tentacles. Small do not develop into large, but represent a distinco
series, really more cirrus-like than tentacle-like.

I

Medusce and Ctenophora 9n

There are no ocelli, or even any visible pigment granules, on the bases of
either class of tentacles.

In the type specimen the manubrium (PL I. fig 4) is almost two-thirds
as long as the bell cavity is deep, flask shaped, with a simple quadrate lip, in
the contracted state tightly closed, its margin smooth, without nematocyst
knobs or swellings.

Gonads: The arrangement of the genital swellings is always an important
character in this family; but in the present case it is impossible to determine
how much they owe to contraction, and in the type (apparently sexually mature)
the genital products apparently occupy the whole interradial walls of the manu-
brium, except for its labial portion (there are no " mesenteries," the manubrium
being quite separate from the subumbrella except at its narrow base), just as is
the case in Heterotiara. Along the four perradii (as revealed by the four corners
of the quadrate lip and the four primary radial canals), there is a narrow band
free from sexual products. In each of the interradii there is a double series of
2-4 oblique folds, better seen in the figure than described: a very simple type
of gonad. But, as noted above, it is a question how far even these folds owe
their existence to contraction. In the other specimen, a female with large
eggs visible, the manubrium is even more contracted, so much so that it is thrown
into a series of irregular folds, and it is impossible to reconstruct its appearance
in life

Colour: In the preserved state both specimens are colourless except for
the manubrium, which, as is often the case, is pale opaque ochre yellow, a tint
which very probably is no index to its colour in life, but merely the result of
preservation.

This new genus agrees so well with the Bythotiaridse in the structure of
its primary tentacles, and their relation to the bell margin, in its manubrium,
and in the departure of its canals from the fundamental Anthomedusan number,
that I have no hesitation in referring it to that family, though in the presence
of two series of tentacles differing structurally as well as in size, it recalls several
typical Pandeids, e.g., Halitiara formosa (Fewkes, 1882, p. 276, Mayer, 1910,
p. 107, pi. 13, fig. 1), Dissonema turrida (1909a, p. 200), Dissonema gaussi
(Vanhoffen 1912, p. 361, PI. I, fig. 2), and Cirrhitiara superba (Mayer, 1910,
p. 126, PL 28, fig. 3; Hartlaub, 1913, p. 284, fig. 237). But it is . sufficiently
distinguished from all Bythotiarids yet known by the presence of eight un
branched canals.

TRACHOMEDUS.E.

Family Olindiidae Browne.

(?) Eperetmus typus Bigelow.

Eperetmus typus Bigelow, 1915, p. 401, pi. 59, figs. 1-8.

Station 200, Port Clarence, Alaska, August 4, 1913, two specimens, about
9 and 7 mm. in diameter, both in poor condition.

These two specimens are only provisionally referred to this species, their
poor condition precluding absolute identification.

In the general appearance of the saucer-shaped bell, with rather long manu-
brium hanging about to the level of the bell opening, they almost exactly re-
produce the type specimen of this species (1915, pi. 59, fig. 1). And while the
small exumbral papillae of the latter are not to be seen here, their apparent
absence may well be due to the fact that they are, apparently, more or less
macerated. The margin of the lip, too, is studded with small sessile nematocyst
knobs, exactly as I have figured it for Eperetmus (1915, pi. 59, fig. 5), especially
evident in the larger specimen, in which the mouth is widely open; and the
gonads, from their large size apparently fully developed in the large specimen,

10n Canadian Arctic Expedition, 1913-18

are of the simple, wavy, leaf-like form characterizing that genus, extending
practically the whole length of the radial canals.

The arrangement and structure of the marginal organs in Eperetmus is
characteristic. And in spite of the poor condition of the present material,
enough tentacles and otocysts are still intact to show the same main features.
Thus the tentacles are all of one kind, corresponding to the primary tentacles
of Olindias, neither the marginal papillae characteristic of Gonionemus, nor the
secondary (velar) tentacles of Olindias occurring. Tentacles are present in all
stages of growth, from mere knobs to the fully developed state. And while the
youngest stand free on the margin, with progressive development they turn
upward against the exumbrella, and finally come to lie in deep furrows in the
latter, from which they project at various heights, corresponding to their ages.
One of the most diagnostic features is the presence of a thick opaque kidney-
shaped nematocyst pad associated with each large tentacle, lining the distal
end of the exumbrellar groove in which it lies (1915). And these pads, being
tough and resistant, are sufficiently preserved to show that in this respect the
present specimens agree exactly with the type. Nor is there any difference in
the structure of the tentacles, which are smooth distally, their outer parts
ringed with nematocyst ridges, without suckers, but terminating in nemato-
cyst knobs. It is not possible to count the tentacles in either specimen, but
to judge from their number in such small segments of the margin as are intact,
there must have been 80-100, i.e., about the same number as in the type speci-
men.

Only a few otocysts are still to be seen. But fortunately such as remain
are large enough to show that they lie in capsules, the various elements of which
are visible even in optical section, and imbedded and entirely enclosed in the
exumbrella, exactly as in the original specimen of Eperetmus. In fact the figures
of the margin of the latter (1915, pi. 59) would equally apply to the present
material. The sense organs themselves are spherical, with central otocyst
mass, borne on a stalk.

In all this our specimens agree perfectly with Eperetmus typus. But it is
impossible to determine whether one of the most important characters of the
latter, the presence of centripetal canals, recurs here. In their present state
the specimens show no clear evidence of them, though in the case of the smaller
one the circular canal in one interradius is apparently dilated centripetally .
But, considering the macerated and rubbed state of the subumbrella, it is an
open question whether such canals were really absent, or whether their apparent
lack is merely the result of mutilation, as so often occurs with these structures
in Liriope. And it is the necessary uncertainty on this point which makes their
identity with Eperetmus typus doubtful, a doubt which cannot be cleared up
till larger and better preserved series are available.

So close is the resemblance between the Port Clarence specimens and the
one known specimen of Eperetmus, even to the most minute details of structure
of the marginal organs, that such divergence as lack of centripetal canals in
the former, would be a somewhat surprising phenomenon. And should it prove
that they are really absent in fact, as well as in present appearance, the generally
accepted classification of the family would demand for them not only a new
species but a new genus.

Family TRACHYNEMID^E Gegenbaur.

Aglantha digitale (Fabricius).
Medusa digitale Fabricius, 1780, p. 366. For Synonymy, see Mayer, 1910, p. 402.

Specimens of this well-known species, all rather fragmentary, were taken at:
Stations 21 a, 6, c, lat. 68° 30' N., long. 166° 32' W., August 15, 1913.
Stations 256, c, off Cooper island, Alaska, surface, August 27-28, 1913.

Medusce and Ctenophora HH

Station 41s, Bernard harbour, Dolphin and Union strait, Northwest terri-
tories, August 24, 1915.

Station 40d (crack in ice), Dolphin and Union strait, Northwest territories,
June 8, 1915.

Station 29^, 50-150 fathoms, crack in ice, lat. 70° 20' N., long. 140° 30' W.,
April 6, 1914. One very fragmentary.

Station 29gr2, 0-150 fathoms, crack in ice, lat. 70° 20' N., long. 140° 30' W.,
April 6, 1914. One very fragmentary.

Station 57a, cape Smyth, point Barrow, Alaska, August 8, 1916. One very
fragmentary.

In all there are perhaps thirty specimens. But for the most part they are
mere shells, minus margin, gonads or manubrium; identified as Aglantha chiefly
on the strength of their rather characteristic outline. In height, such of the
specimens as can be approximately measured range from about 5 to about 15
mm.

Such poor material could not be expected to add anything to our know-
ledge of a species as well known anatomically as is Aglantha digitale, while,
owing to the total destruction of the marginal organs in all the specimens, they
throw no light on varietal differences which have been the subject of much
discussion in this genus. In no case is an otocyst intact.

The records, however, are of interest, geographically, as bridging a gap in
the known distribution of Aglantha, the genus being previously known from
Labrador to the east, Bering sea and off point Barrow (Fewkes, 1885) to the
west of the region in question.

NARCOMEDUS^E.
Family AEGINIDyE Gegenbaur.

Aeginopsis laurentii Brandt.
Plate II, Fig. 3.

Aeginopsis laurentii Brandt, 1838, p. 363, pi. 6, fig. 1-6. For synonymy, see Mayer, 1910,
p. 472, 498.

Station 21 q, 1 fathom, September 26, 1913, off Collinson point, Alaska;
ice, 8 inches; 2 specimens.

Station 27r, 1 fathom, October, 2, 1913, off Collinson point, Alaska; 30° F.
temperature; ice, 10 inches; 1 specimen.

Station 30a; 3 fathoms; May 4, 1914; 69° 41' N., 141° 11' W. Hole made
in ice 6 -feet thick; 1 specimen.

Station 27w, September 19, 1913, off Collinson point, Alaska; ice, 8 inches;
3 specimens.

Station 27n, September 20, 1913, off Collinson point, Alaska; 30° F.; ice,
8 inches; 2 specimens.

The specimens range from 3 to 12 mm. in diameter.

This characteristically arctic, and easily recognized Narcomedusa has been
fully described within recent years by Maas (1916), by Hartlaub (1909), and
by me (1909b). Indeed, since the first account of it, by Brandt (1838), there
has been no doubt of its identity. Its most diagnostic features are the presence
of only four tentacles, but 8 peronii, and the total absence of a peripheral canal
system, contrasted with the presence of 8 bifid, i.e., 16, gastric pouches, the
wrinkled oral surfaces of which bear the genital products, particularly next
their outer margins, which are more or less lobed. There are no otoporpse, but
the otocysts are of the usual Aeginid type, 3 or 4 per octant in the largest speci-
mens, as I have already pointed out (19096, p. 315). All these features are

12n Canadian Arctic Expedition, 1913-18

exhibited by the present series, which, however, add nothing, except by way
of confirmation, to the more extensive series already described and figured l.\
me from the coasts of Labrador and Newfoundland.

Having been recorded from Bering straits on the one hand (Brandt, 1838),
from Labrador and Greenland (Maas, 1906, Bigelow, 19096, Hartlaub, 1909), on
the other, as well as from Barents sea (Linko, 19046; the White sea (Birula,
1896) and from Spitzbergen (Gronberg, 1898, Maas, 1906), its occurrence off
the arctic coast of North America was to be expected. In fact, it is apparently
one of the most characteristic and widespread of Arctic Medusae.

SCYPHOMEDUS.E.

STAUROMEDUS^E.

Family LUCERNARID^E Johnston.
Haliclystus stejnegeri Kishinouye.

Plate II, Fig. 4.
Haliclystus stejnegeri Kishinouye, 1899, p. 126, fig. 1-3, Mayer, 1910, p. 535.

Station 200, port Clarence, Alaska, August 4, 1913; 2-3 fathoms; 2 speci-
mens, both about 12 mm. broad, with well-developed gonads.

Although this genus has been the subject of a great deal of study, not
only from the morphological (Clark, 1863, 1878; Gross, 1900), but also from
the varietal standpoint (Browne, 1895), it is still impossible to draw any
sharp lines between the several species generally recognized.1 This is partly
due to the fact that the various studies on its variations were not undertaken
with this end in view; partly to the homogeneity of the genus as a whole, but
chiefly to the intergrading nature of the characters which have been used to
delimit " species." and to the changes which take place in them with growth
during the normal life of the Medusa, as well as after preservation.

Among the four northern species recognized by Mayer (1910, p. 53),
H. auricula, so fully described by Clark (1878), is recognizable chiefly by the
fact that its eight adradial tentacle-arms are associated in pairs, whereas in
H. octoradiatus, H. salpinx, and H. stejnegeri they stand 45° apart, with the
interradial marginal notches as deep and broad as the perradial. Furthermore,
auricula has more tentacles per arm (100-120) than either octoradiatus or salpinx.
But, like them, the sexual saccules borne by its gonads are arranged in radial
rows, irregular, it is true, but still discernible, there being two rows per gonad
in octoradiatus, 4 in salpinx, 6-8 in auricula. In stejnegeri, on the contrary,
the sexual swellings are in the form of round sacs, of varying sizes, irregularly
arranged over the surfaces of the leaf-like gonads.

The present specimens are identified as stejnegeri, chiefly because they
exhibit the gonad structure supposed to be typical of that species. That is,
each of the eight long leaf-like gonads, which extend from the base of the disc to
the extremities of the arms, is closely studded with a series of globular swellings
varying in size and irregularly arranged (pi. II, fig. 4). Of these there may be
from three or four to nine or ten abreast, and there is no trace of any radial
arrangement in rows, such as characterizes the gonad swellings of H. octoradiatus
and H. auricula (Clark, 1878; Mayer, 1910).

I may also note (as a character separating stejnegeri from auricula) that
the arms in our specimens are 45° apart, the radial and interradial notches
being equally deep and broad.

1 For summary of our present knowledge of this genus, see Mayer, 1910.

Medusce and Ctenophora

13n

On the other hand the peduncle in both specimens is round, instead of
showing the four longitudinal grooves observed by Kishinouye. In other
respects they so closely agree with his description that no further account is
needed here.

The original records of this species being from Bering island, Commander
group (Kishinouye, 1899; Mayer, 1910), the present captures extend its known
range across the breadth of Bering sea. But in this there is nothing surprising,
the Medusa fauna of the latter, so far as known, being decidedly uniform across
its whole breadth (1913).

D-SCOFHORA.

Family PELAGID^E Gegenbaur.
Chrysaora sp.?

Station 42a, Bernard harbour, Dolphin and Union strait (washed up on
beach); September 1, 1915; 1 fragmentary specimen.

Unfortunately this large specimen is now merely a mass of broken fragments,
only the central part of the disc, with the mouth arms, being reasonably intact.
It is impossible to identify it further than that it is certainly a pelagid, and
probably a Chrysaora. Its diameter, when taken, is given in Mr. Johansen's
field notes as 11 inches (about 280 mm.), with mouth arms about 300 mm. and
tentacles about 75 mm. long. The colour is described as follows: " The sixteen
radial stripes and the marginal tentacles were dark brown (the former darkest) ;
gonads and filaments on the four mouth tentacles (arms) light brown; other-
wise the Medusa was pale yellow transparent."

The specimen is now so thoroughly stained with iron rust that no trace
of its normal colouration is to be seen.

Unfortunately this does not suffice to identify the specimen specifically,
for not only are the relationships of the various described members of this genus
still a puzzle, but the colouration of all those of which any considerable number
have been studied, is extremely variable (Mayer, 1910, p. 580). Chrysaora,
though primarily at home in temperate seas, is already known from the sea of
Okhotsk (Kishinouye, 1910, p. 12). And in the North Pacific one or other
" species " of the genus is known from Saghalin island; from Kamtschatka,
the Aleutians, and thence southward to San Francisco bay in California. It
is recorded (C. melanaster) from the neighbourhood of point Barrow (Fewkes,
1885, Murdoch, 1885). It is also recorded from Greenland (Aurivillius, 1896,
fide Morch, 1857). But it is by no means certain that this early record can
be relied on, and it has not been accepted by Kramp (1914).

Family CYANEID^ L. Agassiz.
Cyanea capillata var. capillata (Linnaeus), Eschscholtz.

Medusa capillata Linnaeus, 1758, vol. 1, p. 660. For synonymy and synopsis of varieties,
see Mayer, 1910, pp. 596, 597.

Station 20/, Grantley harbour, port Clarence, Alaska; August 3, 1913;
2 juv. specimens, both about 40 mm. in diameter.

Station 57a, cape Smyth, point Barrow, Alaska, August 8, 1916; 4 young
specimens, 8-20 mm. in diameter, somewhat fragmentary, but yet well enough
preserved to show their identity. At this same locality, according to Mr. Johan-
sen's notes, many Cyanea, large (1-2 feet in diameter) and small were seen,
drifting northward with the strong current.

14n Canadian Arctic Expedition, 1913-18

Both of the larger (but still immature) specimens have lost most of their
mouth parts and tentacles, and are otherwise in poor condition. They are
recorded as belonging to the var. capillata of this widespread and well-known
species, because of their close resemblance to the specimens of C. capillata var.
capillata, which I have previously described from Bering sea (1913, p. 92).
Particularly important, as locating them in this section of the species, are the
facts that the sixteen muscular trapezia of the subumbrella are practically
continuous, one with another, hardly separated at all; and that the clefts
limiting the rhopalar lappets are shallow and the interradial marginal clefts
broad (1913, pi. 4, fig. 8). The arrangement of the lappet canals is likewise
the same as in the Bering sea examples. But they are not in good enough
condition to throw any light on the varietal relationships in this variable genus.
Whatever colour they may have exhibited in life has now disappeared.

Family AURELIID^B L. Agassiz.
Aurelia limbata Brandt.

Aurelia limbata Brandt, 1834, p. 26, Vanhoffen, 1902, p. 43; Maas, 1906, p. 507; Bigelow
1913, p. 99, pi. 5, figs. 1-4. Diplocraspedon limbata Brandt, 1838, p. 372, pi. 10.

Station 20/, Grantley harbour, port Clarence, Alaska, August 3, 1913;
surface; 3 specimens about 75, 50, and 36 mm. in diameter. Also, many noted
as " seen in the water."

These three specimens, the largest of which bears well-developed gonads,
are crumpled and partly decomposed. But the canal system is sufficiently
preserved to show that they are the same form as the specimens from the Aleutian
islands and northern Japan, which I have referred to the A. limbata of Brandt
(1913, p. 99). As I have pointed out, this species (if indeed it deserves so dig-
nified a rank) is separable from the more widely occurring A. aurita chiefly by
the very complex anastomosis of its canals. And though this character is
a trivial one and not sharply defined, thanks to it A. limbata is decidedly
different from A. aurita in general appearance. In the present specimens, as in
the much better ones which I have already described from the Kurile islands,
from the sea of Okhotsk, and from northern Japan (1913, p. 99), the perradial
and interradial groups of canals divide, subdivide, and anastomose so com-
plexly that the entire subumbrella surface is occupied by a close-meshed canal
net. And even the adradial canals, which are straight and unbranched over
their inner halves, take part in the general anastomosis for the outer half of
their length.

A second character which has been used to separate limbata from aurita is
the marginal pigmentation of the former; and this was a striking feature of the
Bering sea series collected by the Albatross (1913, p. 100). In the present case
this pigmentation, if once present, has been lost — probably the result of very
poor preservation. But the Aurelia seen off cape Smyth, point Barrow, Alaska,
station 57a, August 8, 1916 (none preserved) are described by Mr. Johansen as
having the tentacles yellow brown (these, however, may not have been limbata) .
Because of their poor condition the specimens add nothing to previous accounts
of the anatomy of the species. Their principal interest is geographic.

This same variety, or species, of Aurelia, whichever it finally proves to be,
was apparently taken by the Tjalfe expedition in Greenland waters (Kramp,
1913, p. 281), for Kramp's series show the same complex anastomis of the canals
as is characteristic of Aleutian and Bering Strait specimens. Kramp, it is true,
believes that they cannot be referred to limbata, because differing from it in
the degree of pigmentation and outline of the bell. But the structure of the
canals is so much more important than either of these characters that they are

Medusae and Ctenophora 15n

certainly more closely allied to it than to A. aurita. From this it follows that
the arctic Amelia is not only distinguishable from the Aurelia (A. aurita) of
boreal and temperate seas, but, like other Arctic Medusae, is circumpolar.

CTENOPHORA.

CYDIPFIDA.
Family PLEUROBRACHIID^ Chun.

Mertensia ovum (Fabricius).
Beroe ovum Fabricius, 1780, p. 362. For synonymy, see Mayer, 1912, p. 8.

No specimens of this species (at least none recognizable as such) were to
be found in the collection. But it is recorded in Mr. Johansen's field notes as
being common at Camden bay, Arctic coast of Alaska, during September and
October, 1913.

BEROIDA.
Family BEROIDA Eschscholtz.

Beroe cucumis Fabricius.
Beroe cucumis Fabricius, 1780, p. 361. For synonymy, see Mortensen, 1912, p. 83.

Station 57 a, cape Smyth, point Barrow, Alaska, August 8, 1916; 1 small
specimen, about 14 mm. high, and numerous fragments.

The material is not in sufficiently good condition to add anything to the
earlier accounts of this well-known species. For a discussion of its systematic
relationship to the various other " species" of Beroe, I refer the reader to Mor-
tensen (1912).

LOB ATA.

Family BOLINOPSID^ Bigelow.
Bolinopsis sp.?

Bolinopsis (as " Bolina ") is recorded in Mr. Johansen's field notes as
common during September and October, 1913, at Camden bay, Arctic coast
of Alaska. But no specimens were successfully preserved.

GEOGRAPHICAL DISTRIBUTION.

The interest of the present collection is much enhanced by the fact that it is
only the second ever made on the Arctic coast of North America. In fact,
although collections have been made in Bering sea on the one hand (Brandt,
1838; Bigelow, 1913), along the Labrador coast and at various fjords and har-
bours in Greenland on the other, there is not a single record of any Medusa, so
far as I have been able to learn, between Hudson straits on the east, and Ber-
ing straits on the west, except for a few records from the neighbourhood of
point Barrow (Fewkes, 1885; Murdoch, 1885).

The Medusa fauna of the Arctic coasts of Europe, and of Spitzbergen has, on
the other hand, been the subject of such exhaustive study at so many hands
that in its general characteristics it may be regarded as fully as well known as that
of more temperate coasts And the Medusae of the northern coasts of eastern

16n Canadian Arctic Expedition, 1913-18

America are fairly well known, thanks to the southward extension of subarctic
temperatures to New England.

Judging from what is known of the distribution of Medusae in arctic waters
and, indeed, of most other marine organisms, no great faunal peculiarities, dis-
tinguishing the regions studied by the Canadian Arctic Expedition from Bering
sea on the one hand, or from the coasts of Labrador, Greenland, or Spit/bcrgi-n
on the other, were to be expected, the general thesis of the circumpolarity
of most littoral arctic organisms being well established. And, as a matter of
fact, none is shown by the collection, all the Medusae and Ctenophores taken by
the Canadian Arctic Expedition north of Bering straits belonging to species well
known either from some part of the North Atlantic or from its arctic tributaries,
except for the one new species (p. 7n). Such are Sarsia princeps, Sarsia flammea,
Rathkea blumenbachii, Halitholus cirratus, Aglantha digitale, Aeginopsis laurentii,
Chrysaora sp., Cyanea capillata, Mertensia ovum, Beroe cucumis, and Bolinopsis
sp. All of them were living under purely Arctic conditions of temperature,
often, as noted by Mr. Johansen, in the leads and openings in the ice and under
it. And judging from the geographical location of capture, there is no reason
to suppose that any of them are other than endemic to the Arctic ocean, some-
thing which cannot always be said of collections from Spitzbergen, or from
Barents sea. Thus, to take an example, for Chrysaora to have reached Dolphin
and Union strait as an involuntary immigrant from either North Atlantic or
North Pacific waters would require a drift of not less than 1,000 miles; neces-
sarily carried out since the Medusa was set free (Chrysaora passes through a
fixed stage), which, to judge by what is known of the rate of growth of th.e large
Scyphomedusae in cold waters, probably took place not more than three months
prior to its capture. Similarly, it is perfectly safe to conclude that the several
Hydroid Medusae which are evidently common at Collinson point, are normally
at home there. It does not follow, however, that all of them are restricted to
waters of arctic temperature, in their normal distribution. On the contrary,
it is well established that Cyanea capillata among Scyphomedusae, Halitholus
cirratus, Rathkea blumenbachii, and one or another variety of Aglantha digitale
are equally endemic in the boreal waters of the North Atlantic.

It is of great importance, not only to the students of the group, but especially
to the oceanographer, to establish definitely which of the Arctic Medusae are
certainly the products of arctic seas, and of them alone, for such natural buoys
are often of the greatest assistance in indicating the origin, northern or southern,
of the constituent waters of ocean currents. And they have the advantage
over the arctic diatoms, of large size and easy identification. Fortunately
there is at least one Anthomedusa, Sarsia princeps, which has been recorded
from so many parts of the arctic and from the currents flowing from it, e.g.,
the Labrador current, but no where else, that it can safely be taken as a sure
indication of arctic water. Wherever it may drift, it can be as surely retraced
to an arctic home as can a Nova Scotia coast buoy which has strayed out into
the Gulf Stream, to coastal moorings. And no better natural buoy could be
found for not only is its arctic origin certain, and its drift period limited (by the
fixed hydroid stage), but it is so large and its specific features so characteristic
that the veriest tyro could be trusted to recognise it from a good drawing. S.
flammea would perhaps be an equally safe index to arctic waters, except that it
is less distinguishable from its relatives.

Among Leptomedusae I may mention, as an arctic index, Ptychogena lactea
(not, however, represented in the present collection). Typically arctic Tra-
chomedusae are Ptychogastria polaris (1909b, 1913.) and Botrynema elinorce (Hart-
laub, 1909; Bigelow, 1913, p. 52).1

MSince Ptychogastria polaris lives, as a rule, on or close to the bottom, and often in enclosed
waters, it is less apt to be of service to the oceanographer than the surface forms.

Medusce and Ctenophora 17n

One Narcomedusa, Aeginopsis laurentii, is likewise typically arctic. And,
like Sarsai princeps, it is not only large but very easily recognized; and it is
now known from so many records, so widely distributed over the Arctic seas,
that its presence can be considered a sure indication of arctic water.

This is equally true of the Ctenophore Mertensia ovum, which is not only
a true arctic form, but is so sensitive to changes of temperature that it does
not long survive any considerable warming of the water in which it floats (1917,
p. 249).

If further confirmation of the affinities of Sarsia princeps, Sarsia flammea,
Aeginopsis, and Mertensia be needed, it is furnished by the collection of the
Canadian Arctic Expedition, as it is for their circumpolarity. Indeed, to find
any shallow-water arctic Medusa not circumpolar would be surprising, there
being no barrier, either in the physical conditions of the sea water or in the
presence of a land mass, to such distribution.

So far as the present collection goes, it may be considered a typical repre-
sentative of the endemic littoral Medusa fauna of the Arctic.

POSTSCRIPT

LIST OF MEDUSAE COLLECTED BY THE CANADIAN EXPLORING STEAMER
" NEPTUNE " 1903-1904.

The few Medusae taken during this expedition are in poor condition, and,
as all belong to well-known species, a simple list of the records is given.

Catablema vesicaria (A. Agassiz).

One specimen, 20 mm. in diameter, with thirty large tentacles (all broken
off short) and about as many knobs, from Black Tickle, Labrador, September,
1903.

Aglantha digitale (Fabricius).

Three specimens, very fragmentary, 20-25 mm. high, port Burwell, Ungava,
September, 1903.

Cyanea sp.?

One specimen, about 35 mm. in diameter, too fragmentary for more than
generic determination, Fullerton, west side of Hudson bay, Northwest Terri-
tories, September, 1903.

Aurelia limbata Brandt (?)

Seven small specimens of Aurelia, 20-30 mm. in diameter, probably be-
longing to this species, because of the anastomosis of the canals (p. 14n), from
Black Tickle, Labrador, September, 1903. One specimen of about the same
size from North Somerset, Northwest Territories, August, 1904.

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1904. Me"duses provenant des campagnes des yachts " Hirondelle " et "Princess-Alice"
(1886-1903). Result, camp. sci. Monaco, fasc. 28, 71 pp., 6 pis.

Medusa arid Ctenophora 19n

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14 pis.

1906. Die Arktischen medusen Fauna Arctica, 4, pp. 479-526.

1909. Japanische medusen. Abh. K. Bayer, akad., suppl. 1, pt. 8, 52 pp., 3 pis.
Mayer, A. G. —

1910. Medusae of the world. Carnegie Inst. publ. No. 109, 3 vols., 735 pp., 76 pis

1912. Ctenophores of the Atlantic coast of North America. Carnegie inst. publ. No. 162,

58 pp., 17 pis.
Mortensen, T. —

1912. Ctenophora. Danish Ingolf exped., 6, No. 2, 95 pp., 10 pis., 1 chart.
Murbach, L., and Shearer, C. —

1903. On Medusae from the coast of British Columbia and Alaska. Proc. Zool. Soc.,

London. 2, pp. 164-192, pis. 17-22.
Murdoch, J. —

1885. Notes on surface life . . . Kept. Int. Polar Exped. to Point Barrow, Alaska.

Pt. 4, appendix, pp. 193-200
Rathke, M. H.—

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20H

Canadian Arctic Expedition, 1913-18.

EXPLANATION OF PLATES.

All figures drawn from photographs by E. N. Fischer.

PLATE I.

Fig. 1. Sarsia princeps Haeckel. Side view of. specimen 18 mm. high. It has swallowed a
Schizopod.

Fig. 2. Halitholus cirratus Hartlaub. Side view of specimen 13 mm. high.

Fig. 3. Halitholus cirratus Hartlaub. Side view of specimen 14 mm. high with bell cavity
opened, and upper wall turned back, to show manubrium and gonads.

Tig. 4. Eumedusa similis, gen. et sp. nov. Side view of type specimen, with half the bell wall
cut away, to show manubrium and gonads. Four radial canals are intact, and the
base of a fifth.

Fig. 5. Eumedusa similis, gen. et sp. nov. Apical view of contracted specimen (p. 8H.) to
show the 8 radial canals.

Plate No. 1

22H

Canadian Arctic Expedition, 1913-18.

PLATE II.

Fig. 1. Eumedusa similis, gen. et sp. nov. Oral view of segment of margin of type specimen,
to show the two classes of tentacles, large hollow and small solid.

Fig. 2. Eumedusa similis, gen. et sp. nov. Side view of segment of margin of type specimen
showing relation of large and small tentacles to margin and ex-umbrella.

Fig. 3. Aeginopsis laurentii Brandt. Oblique side view of specimen 12 mm. in diameter.

Fig. 4. Haliclystus stejnegeri Kishinouye. Segment of gonad, to show arrangement of genital
swellings.

Fig. 5. Sarsia flammea Linko. Side view of specimen 8 mm. high. From a photograph.

Plate No. 2

*n

Report of the Canadian Arctic Expedition, 1913-18

VOLUME Vm: MOLLUSKS, ECHINODERMS, COELENTERATES, ETC.

Part A: MOLLUSKS, RECENT AND PLEISTOCENE. By William H. Dall.

Part B: CEPHALOPODA AND PTEROPODA.

Cephalopoda. By S. S. Berry-Berry.

Pteropoda. By W. F. Clapp ....................................... (In preparation)

Part C: ECHINODERMS. By Austin H. Clark. ...... ........... . . (Issued April 6 1920).

Part D: BRYOZOA. By R. C. Osburn .............. . ........... (In preparation).

Part E: ROTATORIA. By H. K. Harring ..................... (In preparation)

Part F: CHAETOGNATHA. By A. G. Huntsman ........ (In preparation).

Part G: ACTINOZOA AND ALCYONARIA. By A. E. Verrill .......... . (In press).

Part H: MEDUSAE AND CTENOPHORA. By H. B. Bigelow .............. (Issued June SO ? 1920).

Part I: HYDROIDS. By McLean Fraser ................ (In preparation).

Part J: PORIFERA.

VOLUME IX: ANNELIDS, PARASITIC WORMS, PROTOZOANS, ETC.

Part A: OLIGOCHAETA.

Lumbriculidae. By Frank Smith.

Enchytraeidae. By Paul S. Welch ............................. (Issued September 29, 1919).

Part B: POLYCHAETA. By Ralph V. Chamberlin. . ........... (In press).

Part C: HIRUDINEA. By J. P. Moore ............... ............................. (In preparation).

Part D: GEPHYREA. By Ralph V. Chamberlin ............................... (Issued June 80, 1920).

Part E: ACANTHOCEPHALA. By H. J. Van Cleave .......................... (Issued April 7, 1920).

Part F: NEMATODA. By N. A. Cobb ................ .; ............................. (In preparation).

Part G-H: TREMATODA AND CESTODA. By A. R. Cooper. . . ..(In press).

Part I: TURBELLARIA. By A. Hassell ........................... . ....... . . (/„ preparation).

Part J: GORDIACEA.

Part K: SPOROZOA. By J. V. Mavor .................................. . ............ (In preparation).

Part M: FORAMINIFERA. By J. A. Cushman ...... ....................... (Issued February 6, 1920).

VOLUME X: PLANKTON, HYDROGRAPHY, TIDES, ETC.

Part A: PLANKTON. By Albert Mann ......... ..(In preparation).

Part B: MARINE DIATOMS. By L. W. Bailey ........ ..(In preparation).

Part C: TIDAL OBSERVATIONS AND RESULTS. By W. Bell IDavrson.. (Issued October 1, 1920).
Part D: HYDROGRAPHY ......................... . .............................. '..(In preparation).

VOLUME XI: GEOLOGY AND GEOGRAPHY

Part A: THE GEOLOGY OF THE ARCTIC COAST OF CANADA, WEST OF THE KENT
PENINSULA. By J. J. O'Neill. . ........................ ................ (In preparation).

Part B: MAPS AND GEOGRAPHICAL NOTES. By Kenneth G. Chipman and John R. Cox.

(In preparation) .
VOLUME XII: LIFE OF THE COPPER ESKIMOS

THE LIFE OF THE COPPER ESKIMOS. By D. Jenness .................... (In press).

VOLUME XHI: PHYSICAL CHARACTERISTICS AND TECHNOLOGY OF THE

COPPER ESKIMOS

Part A: THE PHYSICAL CHARACTERISTICS OF THE COPPER ESKIMOS. By D.
Jenness (in part) ............................... ' .................. ' .......... (In preparation) .

Part B: TECHNOLOGY OF THE COPPER ESKIMOS ......................... (To be prepared).

VOLUME XIV: ESKIMO FOLK-LORE AND LANGUAGE

Part A: FOLK-LORE, WITH TEXTS, FROM ALASKA, THE MACKENZIE DELTA, AND
CORONATION GULF. By D. Jenness ................................. (In preparation).

Part B: COMPARATIVE GRAMMAR AND VOCABULARY OF THE ESKIMO DIALECTS
OF POINT BARROW, THE MACKENZIE DELTA, AND CORONATION GULF.
By D. Jenness ............................................................ (In preparation).

VOLUME XV: ESKIMO STRING FIGURES AND SONGS

Part A: STRING FIGURES OF THE ESKIMOS. By D. Jenness ............... (Ready for press).

Part B: SONGS OF THE COPPER ESKIMOS. By D. Jenness (in part) ......... (In preparation).

VOLUME XVI: ARCHAEOLOGY

CONTRIBUTIONS TO THE ARCHAEOLOGY OF WESTERN ARCTIC AMERICA.
......................................................................... (To be prepared).