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KONGL. SVENSKA VETENSKAPS-AKADEMIENS HANDLINGAR. Bandet 18. N:o 5.

-TJ

C<^

ON SOME NEW AND LITTLE KNOWN DIATOMS

BY

b

.^PJ

P. T. CLEVE.

WITH SIX PLATES.

JO

3x

\

COMMUNICATED TO THE ROYAL SWEDISH ACADEMY OF SCIENCES SEPTEMBER 15, 1880.

\

STOCKHOLM, 1881.

KONGL. BOKTRTCKERIET.

p. A. NORSTF.nl & SONEB.

Oeveral years ago I received through Professor S. Loven from the Swedish State
Miiseuin some samples af shellsand and mud, which had been collected during the ex-
pedition of the Roy. Swedish Fregate Eugenie 1851 — 53 on the Gallapagos Islands,
Honolulu, Port Jackson etc. On examining these samples, as well as many others,
received from various friends and correspondents, I found a number of diatoms, which
seems to me to be entirely new to science or at least of interest. Especially am I in-
debted to Dr. SoDERLUND for some very rich materials from the Mediterranean Sea and
the Balearic Islets, to Mr. Christian Febiger, the wellknown diatomist of Wilmington,
Delaware, Mr. Hauck of Triest, Prof. Berggren, Dr. 0. Nordstedt and others for va-
rious interesting gatherings. Mr. Gkunow of Vienna has kindly helped me in preparing
this paper and assisted me in many cases of uncertainity, and for which I here take
the liberty of tendering him my best thanks.

Mastogloia Thwaites.

1. M. imnduriformis Cl. N. Sp.

Valve panduriform with cuneate ends. Margin with somewhat distant loculi, ex-
cept in the middle, on both sides of the central nodule, where they are wanting or
indiscernible. The surface of the valve is covered with small, irregularly scattered
])uncta and very tine (20 in 0,01 mm.), parallel, punctate striae These stria3, which are
not strongly marked, cover the whole valve, except a small area, round the straight
median line and central nodule. Terminal nodules turned in opposite directions.

Lcncrth 0,0975 mm. Breadth 0,027 mm. at the constriction 0,0195 mm.

Gallapagos Islands (Eugenie Exp.) Very rare.
PL I, fig. 1, ^°%.

The outline of the frustule, the few and large loculi as well as its i)eculiar
structure destinguishes this tine form from all previously known species. Its nearest
allies are the Navicula; or Mastogloiie, forming A. Schmidts section Pseudodiploneis,
A', marginata Lewis, N. straiu/ulatd Grev., lU a stag I.? reliadatn GiiUN.

4 p. T. CLEVE, ON SOME NEW DIATOMS.

2. Mastogloia submarginata Cl. et Grun. N. Sp.

Elliptic lanceolate, ends neither produced nor capitate. Marginal loculi very in-
distinct, 5 — 8 in 0,01 mm. Stria? punctate, 18 — 20 in 0,01 mm., most strongly marked
near the margin and on both sides of the median line, so that they seem to be inter-
rupted by a more or less large lunate area. The stria? continue across this area, but
are very faintly marked, and can only be discovered with good objectives.

Length 0,04-0,048 mm. Breadth 0,013—0,017 mm.

Gallapagos Islands (Eugenie Exp.), Campeche Bay (accord, to Geunow).
PI. I, %. 2, "°%.

The specimens from Gallapagos Islands have 18 stria; and 8 canaliculi in 0,01 mm.,
specimens from Campeche Bay, according to Grunow, 20 striae and 5 — 7 canaliculi. In
its very indistinct canaliculi and the interi'upted stria? this species comes nearest to
N. Jelineckii Grun.

Amphora Ehb.

1. A. Berggrenii Cl. N. Sp.

Median band not complex, central nodule not transversely dilated. The frustule
is elongated with broad and rounded ends and almost parallel sides; its form being-
like that of A. arenaria Donk. The valve is striate, dorsal stria? almost parallel, more
distant in the middle (17 in 0,01 mm.) than near the ends (20 in 0,01 mm.); ventral
stria? irregular, divergent, especially near the terminal nodules. Terminal nodules con-
spicuous and seem to project into the frustule.

Length of the frustule 0,065 mm. Breadth 0,025 mm.

Fossil, Arthurs Pass, New Zeeland, mixed with freshwater species, such as Navi-
cula serians, N. rhomboides, N. cuspidata etc. S. Berggren.
PI. I, fig. 3, "°7i; a. valve, b. frustle.

A freshwater species of Amphora having this appearance is very remarkable. I
have issued this species in Cl. et Moll. Diat. N:o 90.

Cymbella Ag.

1. Cymbella Brasiliana Cl. N. Sp.

Almost symmetrical, naviculoid (a faint obliquity being percebtible only on large
specimens), lanceolate with somewhat obtuse apices. Median line straight. Stria? ra-
diant, near the apices almost parallel, covering the whole surface, except a narrow
(larger near the central nodule), area round the median line. The central stria; are
stronger and more marked than the others. All the stria? are punctate, the puncta
forming waAvy longitudinal lines. Stria? 22 in 0,01 mm. on the part between the
middle and the ends.

KONliL. SV. VET. AICADEMIENS HANDLINGAK. BAND. 18. NM 5. 5

Length 0,035 -0,06 mm. Breadth 0,012-0,015 mm.

PI. I, tig. 4, a. (dry), 6. (balsam); ""7,.
Brazil, fresh water, collected by Dr. Warming. (Cl. et Moll. Diat. N:o 193.)
In the strongly marked central striae this form reminds one oi Navicula Crucicula,
but it is quite different. There is also some resemblance to the Navicula Lundstrbmii
Cl. (in Cl. et Gkun. Arctische Diat. PI. Ill, fig. 39). Another allied form is the as
yet undcscribed Cymhella Fricseana Grun. from Tana Elf in Finmarken (Cl. et Moll.
Diat. N:o 261). This species has produced and capitate ends and 12 — 15 punctate
striif in the middle, 18 — 19 halfway between the middle and the ends, where they are
21 in 0,01 mm. Length 0,05 — 0,06 mm. Breadth 0,014 mm.

2. Cymhella Stodderi Cl. N. Sp.

Elongate, lanceolate, slightly asymmetrical. Ends slightly produced and attenuated.
Striae strongly radiant in the middle, almost parallel near the apices, scarcely punctate,
10 in 0,01 mm. a little more distant in the centre, covering Va of the valve and
leaving on both sides of the median line a tolerably broad area.

Length 0,075—0,09 mm. Breadth 0,015 mm.
PI. I, tig. 5; ""'7, (Specimen from Brazil).

Fossil: Beniis Lake in White Mountains (Mr. Stodder). Living: Brazil, Minas
Geraes on Sphagna leg. Dr. Hj. Mosen.

This species, which occurs in Cl. et Moll. Diat. N:o 212 and N:o 274, is most
nearly related to the C. Americana A. Schm. Atl. PI. IX, tig. 15 and 20, but the latter
form has a more narrow area and, as fig. 15 shows, punctate striae.

Pleiirosigma W. Sm.

1. Pleurosigma tortuosum Cl. N. Sp.

Median line strongly and equally sigmoid. Stritc in three sets, oblique 21, trans-
verse 22 in 0,01 mm.

Length 0,076 mm. Breadth 0,008 mm.

PI. I, fig. 6; "°%.
Balearic Islets (Dr. Soderlund) rare.

2. Pleurosigma lanceolatum var. cuspidatum Cl.

Lanceolate with produced apices, symmetrical. Median line straight, the ends
turned in opposite directions. Striae in three sets, one transverse (20 in 0,01 mm.)
and two oblique (22 in 0,01 mm.).

Length 0,083 mm. Breadth 0,02 mm.
PL I, fig. 7; ''"'7i- l>. structure; -'"'7i.

Marine: Port Jackson (Eugenie Exp.).

The same variety from Newcastle has according to Grunow 20 transverse and 19
oblique striaj in 0,01 mm. Length 0,105 ram. Breadth 0,026 mm.

6 p. T. CLEVE, ON SOME NEW DIATOMS.

3. Pleurosigmn (Donkinia?) longissimum Cl. N. Sp.

Very long and narrow, linear; ends obtuse. Median line straight in the middle
but curved in the last third part from the central nodule. Stria3 in two sets crossing
each other in right angles, transverse I8V2, longitudinal 21 in 0,01 mm. Colcur
pale straw.

Length of the frustule 0,17 mm. Breadth 0,0083 mm.
PL I, fig. 8. a. ''"/,; h. structure ='""7,.

Balearic Islets rare (leg. Dr. Soderlund).

Rlioicosigma Grun.

1. Rhoicosignia mediterraneuin Cl. (in Grun. Micr. Journ. 1877, p. 182).

Narrow lanceolate, with acute ends. Median line strongly bent in the first third
part from the central nodule, afterwords straight. Stria; longitudinal and transverse.
The longitudinal striai are very fine, about 27 in 0,01 mm., the transverse I8V2 i"
0,01 mm.

Length 0,18—0,21 mm. Breadth 0,0225 mm.

PI. I, fig. 9, '"A. a. and h. valves, c. structure '""V,.

Balearic Islets rare (leg. Dr. Soderlund).

Navicula Boky.

1. Navicula {Fluminensis var. ?) Floridana Cl. N. Sp.

Elongated, slightly constricted in the middle, ends rounded. Stria; not distinctly
punctate, parallel, 15 in 0,01 mm., closer near the ends, 20 in 0,01 mm., absent from
the middle part of the valve, not reaching the median line, which is surrounded by a
narrow, linear area.

Length 0,045—0,075 mm. Breadth 0,01-0,012 mm. at the constriction 0,08—
0,009 mm.

PI. 1, fig. 10, ^»»7x.

Florida coast, near Pensacola Harbour (in a gathering sent by Mr. Febiger).

2. Navicula cruciata Cl. N. Sp.

Oblong, slightly contracted at the centre. Stria3 12 in 0,01 mm., [)arallel, costate,
smooth or indistinctly granulate, absent from the middle part of tiie valve, not
reaching the median line.

Length 0,087 mm. Breadth 0,017 mm. at the middle 0,014 mm.

PI. I Fig. 11, '""7..

I have found this species in a sample, said to be from Greenland, but as it con-
tained many tropical forms, I am not sure that this is correct.

KONGL. SV. VET. AKADEMIKNS HANDUNGAK. BAND. 18. N:() 5. 7

3. Navicula Grcenlandica Cl. N. Sp.

Lanceolate with obtuse apices. Striae coarse, costate, very radiant and divergent,
crowded around the centre of the valve (T'^ i» 0,01 mm.) more distant between the
centre and the ends ((> in 0,01 mm.), interrupted by furrows, parallel to the margins.
Around the central nodule there is a very large orbicular area.

Length 0,117 ram. Breadth 0,023 mm.
PI. I, tig. 13, '""V..

Greenland, Davis Strait (very rare in Cl. et Moll. Diat. N:o 172).

In its characters this species approches N. Trevelyana, but its form is entirely
different. The striaj are also more distant, being in N. Trevelyana 10 in 0,01 mm.
The terminal nodules of N. Gvcenlandia are peculiar and resemble those of N. Rec/vla
Cl. et Grdn. (Cl. W. Ind. Diat. p. 5, PI. 1, fig. 3.)

4. Navicula Etigeniw Cl. N. Sp.

Valve very convex, linear, with rounded ends. Stria' coarse, costate, radiant, 9
in 0,01 mm., reaching the median line, interrupted by a line parallel to the margin.
Median line undulate. Central nodule surrounded by a small area. Terminal -nodules
elongated. — F. V. Frustule constricted in the middle; ends truncate.

Length 0,085—0,1 mm. Breadth 0,017 mm.
PI. II, fig. 16, '""7., a. S. v., h. F. V.

Gallapagos Islands (Eugenie Exp.).

5. Navicula Hennedyi var. undidata Cl.

Oval with cunate ends and three undulations on each side. Stria? distinctly punc-
tate, marginal and around the median line. The striae near the uiedian line are 16 in
0,01 mm. as are also the marginal stria;, except in the constrictions between the un-
didations, where they are only 12 in 0,01 mm.

Length 0,07 mm. Breadth 0,035 mm.
PI. II, fig. 19, '""Vi-

Gallapagos Islands (Eugenie Exp.).

This variety has finer strije thiin the other forms of the most variable N. Hen-
nedyi; the outline is also different.

N. Hennedyi var. minuta Cl.

Broadly oval, with the marginal punctate stria; (7—8 in U,01 mm.) separated
from each other by unusually large spaces. Central stria? 9 — 10 in 0,01 ram.

Length 0,05 mm. Breadth 0,027 mm.
PI. I, fig. 15, '"»7..

Gallapagos Islands (Eugenie Exp.).

8 p. T. OLEVE, ON SOME NEW DIATOMS.

N. Hennedyi var, Tahitensis Cl.

Broadly oval with almost parallel sides. Stride scarcely punctate, marginal 13 in
0,01 mm., central 15 in 0,01 mm.

Length 0,05 mm. Breadth 0,023 mm.

PL I, fig. 14, -»%.
Tahiti (Eugenie Exp.).
This variety is remarkable for its almost smooth striae.

6. Navicula rudis Cl. N. Sp.

Broadly oval, with broadly rounded ends. Strias coarse, 6 in 0,01 mm. marginal
composed of about 5 — 8 large, separate puncta; central stria) composed of 2 — 3 puncta.
Length 0,052 mm. Breadth 0,032 mm.
PL II, fig. 17, '""Vx.
Balearic Islets rare (leg. Dr. Soderlund).

This peculiar form belongs evidently to the Nav. Lyra section. It approaches in
some respects N. spedabilis Greg, and N. prcetexta Ehb., but it differs of both.

The numerous forms, belonging to this section, are so closely allied, that it is
impossible to decide what are species or what varieties. Another most beautiful and
gigantic form of this section is the following:

7. Navicida {excavata Grev. var.?) Angelorum Cl.

Very large, broadly oval, with rounded ends. Area large bilobate. Striaj pun-
ctate, radiant, 6V2 '" 0>01 ntmi- (8 near the ends). Central striae 11 72 i" O^Ol "fUT'-
Length 0,22 mm. Breadth 0,12 mm.

PL II, fig. 20, «"7i.
Fossil: California, Sancta Monica los Angelos (comm. by Dr. G. Eisen).

8. Navicula Holmiensis Cl.

Valve large, oblong elliptic, with rounded ends. Striae slightly radiant, 12^/^ in
0,01 mm., indistinctly punctate, covering a little more than half the valve and leaving
round the median line an irregular area.

Length 0,07—01 mm. Breadth in 0,023 mm.
PL II, fig. 18, "»%.

Slightly brackish water near Waxholm (entrence to Stockholm) leg. Lagerstedt
and 0. Nordstedt.

This form agrees in general appearance with N. latiuscida KtlTZ. {N. patula W.
Sm.), but has more distant striae, which in N. latiusculn are 18 in 0,01 mm. and pa-
rallel.

KONGL. SV. VET. AKAPEMIENS IIANnLINaAK. BAND. 18. N:0 5. 9

9. Navicula Platessa Cl. N. Sp.

Small, broadly elliptic, with mucronate apices. Striju strong, smooth, 8 in 0,01
mm., marginal, leaving around the median line a very large area.
Length 0,028 mm. Breadth 0,018 mm.

PI. I, iig. 12, '"«%.
Gallapagos Islands rare (Eugenie Exp.).

This little Navicula belong to the Palpebralis-group, but differs from all de-
scribed forms of that section by its short, distant and coarse stri*.

10. Navicula Haiiekii Cl. N. Sp.

Very long and slender, linear, somewhat gibbous in the middle and near the
ends, convex. Stride punctate, 15 in the middle of the valve, 16 towards the ends and 18
in 0,01 mm. in the ends, a little shortened around the central nodule and not reaching
the median line, which is surrounded by a linear area. The stria3 are interrupted by
a very fine line parallel with the margin.

Length 0,128 mm. Breadth 0,012 mm.
PL II, fig. 27, ^""A.

Adriatic Sea, Rovigno, stomachs of Holothurians. leg. F. Hauck (rare in Cl. et
Moll. Diat. N:o 208—210).

This species seems to belong to the section A^av. liinosai and is allied to N. ma-
xima, N. formosa etc.

11. Navicula Fehigerii Cl. N. Sp.

Lanceolate, with produced, obtuse ends. Stria? 16 in 0,01 mm., composed of
distinct puncta, reaching the median line. In the middle they are alternately longer
and shorter around the central nodule, which is surrounded by a broad area.

Length 0,054 mm. Breadth 0,02 mm.

PI. II, fig. 21, '""V,.

Oakland Bridge, California in a sample sent by Mr. Cim. Febiger.

This beautiful little species has some resemblance to Achnanthes Danica (FlOgel)
Grun., but seems to be a true Navicula, belonging to the section »punctata3".

12. Navicula Cluthensis var.? maculifera Cl.

Broadly oval, with rounded ends. Stria? radiant, reaching the median line, ab-
breviated around the central nodule, which is surrounded by a tolerably large area.
Number of stria3, (Avhich are composed of distinct puncta), 11 — 12 in 0,01 mm.
Length 0,05 mm. Breadth 0,026 mm.

PI. II, fig. 23, "»7,.
Slightly brackish water, near Waxholm, entrance to Stockholm (Mr. Lagerstedt).
This form has closer strite than the typical species and an ai^ea around the no-
dule. Another smaller foru) is probably.

2

K. Sv. Vet-Ak.ad. Hancil. Band. IS. N:o 6.

10 p. T. CLEVE, ON SOME NEW DIATOMS.

N. Clutheiisis var. minuta Cl.

Broadly oval, with rounded ends. Striae slightly radiant, composed of distinct
puncta, abbreviate around the central nodule, 15 in 0,01 nun. in the middle, 18 in
0,01 mm. in the ends.

Length 0,03 mm. Breadth 0,014 mm.
PI. II, fig. 22, '""V,.

Florida, Pensacola in a gathering, sent by Mr. Chr. Febiger.

The following varieties of N. Cluthensis are described:

a. genuina (Greg. Diat. of Clyde p. 6, PI. I, fig. 2) with 8 striag in 0,01 mm
and no area. Length 0,035 — 0,04 mm.

b. eiythrcea (iV. erythrcea Grun. Verb. 1860 p. 539, PI. Ill, fig. 17) with 10—12
stria; in 0,01 mm. and no area. Length 0,05 — 0,06 ram.

f. FinmarcJiica Grun. (in Cl. et GruN. Arct. Diat. p. 40, PL II, fig. 49) with
11 — 12 striiB in 0,01 mm. and very small area. Length 0,022—0,024 mm.

d. macuUfera Cl. with 11 stria? in 0,01 mm. and tolerably large area.

e. minuta Cl. with 15 — 18 stria? in 0,01 mm. and tolerably large area.

13. Navicula hicuspidata Cl. et Grun.

Oblong, slightly constricted in the middle, apiciilate. Stria' coarse, finely pun-
ctate, 6 in 0,01 mm., shortened around the middle.

Length 0,04 ram. Breadth 0.015 ram.
PI. II, fig. 25, '"»%.

Mediterranean, Pithuisian Islands in a gathering sent by Prof. V. B. Wittrock.

The nearest allied to this species seems to be Nav. directa Sm. The Nav. salva
A. ScHM. and Nav. opima Grun. have the terminal nodules at some distance from the
apices.

14. Navicula mesoleia Cl. N. Sp.

Very convex, linear with cuneate ends. Stria? coarse, 15 in 0,01 mm., very
slightly radiant, almost reaching the median line, absent from the raiddle of the valve,
where there is a transverse blank space.

Length 0,04—0,06 mm. Breadth 0,005—0,008 mm.
PL II, fig. 26 a and b, '""/,.

Fresh water, Brazil, leg Dr. Warming. (Cl. et Moll. Diat. N:o 193.)

This form has the appearance of some smaller varieties of N. Pinnularia Cl.
(Cl. et Grun. Arct. Diat. p. 27) but is more convex and has closer stria?.

15. Navicula Fromentera' Cl. N. Sp.

Small, elliptic. Stria? coarse, costate, 6 in 0,01 mm., reaching the median line,
but abbreviated around the nodule.

Length 0,0375 mm. Breadth 0,0128 mm.

PL II, fig. 24, '""y,.
Balearic Islets (F. Soderlund).

KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 18. N:0 5. 11

This suuill species seems to be the unnamed form in A. Schmidts Atlas PI. 46, tig. 7
and is perhaps according to Grunow the iV^. mediierranea Kutz. Bae. PI. Ill, iig. XVII,
which however is represented on much too small a scale to adinet of identification.
Another allied form is the yet unpublished J^. cotiformis Grun. from Demerara River,
which has cuneate ends and 5 striae in 0,01mm. Length 0,06 mm. Breadth 0,014 mm.

16. Navicula Anderssonii Cl. N. Sp.

Linear oblong, with almost cuneate ends. Stri:e parallel or slightly radiate in
the middle, 6V2 — 7 in 0,01 mm. not reaching the median line, which in surrounded by
a narrow area, dilated around the central nodule.

Length 0,075 mm. Breadth 0,019 mm.
PL m, fig. 28, '""%.

Gallapagos Islands (Eugenie Exp.).

I have named this species in honour of the late Prof. N. J. Andersson, botanist
to the Eugenie Expedition.

17. Navicula margimdata Cl. N. Sp.

Rhombic; strire very short, marginal, enclosing a large structureless area, 17 in
0,01 mm.

Length 0,042 mm. Breadth 0,012 mm.

PI. Ill, fig. 29, ^""7,-
Florida, near the Harbour of Pensacola, in a gathering sent by Mi\ Febiger.

18. Navicida {Pon-elli Lewis var.) GaUapagensis Cl.

Linear oblong with cuneate ends. Striaj coarse, almost parallel, 8V2 i" *^!01 mm.,
on both side of the median line interrupted by linear areas. There are thus four lon-
gitudinal series of short striaj, two near the margins and two close to the median line,
interrupted near the central nodule.

Length 0,05—0,09 mm. Breadth 0,013—0,021 min.

Gallapagos Islands (Eugenie Exp.).
PI. III. fig. 30.

Of the true N. Poioellii Lewis I have not seen a figure, but Grunow states that
his A'. Vidowichii (Verb. 1863, PI. IV, fig. 4) is the same species. I have seen the latter
form in gatherings from Adriatic sea, kindly sent me by Mr. F. Hauck, and I find
that the form is different, the stria?, more distant (6 in 0,01 mm.)- Length 0,1122 mm.
Breadth 0,02 ram. N. Egyptiaca Grev. Trans. Micr. Journ. XIV, p. 127, PI. 12, fig.
16 — 17 seems to l)e the same, but tlie strise are stated to be only 4 in 0,01 mm. An-
other allied form is, as far on may judge from the figure, N. Zanardiniana Grun.
(Verb. 1860, PI. 3, fig. 12) with indistinctly punctate stria?, 6 in 0,01 mm., in four
uninterrupted rows. Another, undescribed form is A^. Wittii Grun. Mspt. (PI. Ill, fig.
31, ""Vi) from Brazil, which is lujt so long and slender as the last named species and
has 8 striie in 0,01 mm: Tlie two following forms are also iillied to A'^. Powellii.

12 p. T. CLEVE, ON SOME NEW DIATOMS.

19. Navicula arnica Cl. et Grun.

Contracted in the middle, ends cuneate; stria? 7V2 in 0,01 mui., almost parallel,
smooth. The two interior rows of striaj are interrupted in the middle.
Length 0,075 mm. Breadth 0,023 mm.

PI. Ill, fig. 37, "'7,-
Tahiti (Eugenie Exp.).

20. Navicula quadriseriata Cl. et Grun.

Large, oblong oval with parallel sides and cuneate ends. Stria; smooth, 8 in 0,01
mm. in four longitudinal, uninterrupted rows. The interior striaj are shortened around
the central nodule, which is surrounded by an orbicular area.

Length 0,09 mm. Breadth 0,035 mm.
Pl.III, fig. 32, ««%.

Balearic Islets very rare (F. Soderlund).

Two other species, of which Mr. Grunow has sent me figures, seem to be related
to the last described forms: N. Castracanei Guvi!i. (PL III, fig. 33, "°7i) and JSf. Petitiana
Grun. (PI. Ill, fig. 34, '°7i)- Both species are elliptic lanceolate and have the interior
rows of stria) parallel with the margins of the valve, not close to the median line.
N. Castracanei is 0,1 mm. in length, 0,03 mm. in breadth, and has 9 stria; in 0,01 mm.
N. Petitiana is 0,07 mm. in length and 0,02 mm. in breadth and has 11 stria; in
0,01 mm.

All these species together with the following seem to form a section, for which
Mr. Grunow has proposed (Cl. et Grun. Art. Diat. pag. 29), the name quadri-seriatce :
This group contains:

Navicula Powellii Lewis — N. Vidowichii Gkun.

N. Egyjitiaca Grev.

N. {Powellii var.) Gallapagensis Cl.

JV^. Zanardiniana Grun.

N. Wittii Grun.

N. arnica Cl. et Grun.

N. quadriseriata Cl. et Grun.

N. Castracanei Grun.

N Petitiana Grun.

? N. {Stauroneis) robusta Petit (Diat. de Tile Campbell PI. V, fig. 16).

N. biseriata Petit (1. c. PL IV, fig. 15).

N. Richardsoniana O'Meara (Irish Diat. PI. 31, fig. 33).

N. Eugenice Cl. (this paper pag. 7).

? N. denticulata O'Meara (Quart. J. M. S. VII, p. 115, PL V, fig. 2, 1867).

? N. Musca Ehb.

? N. mirabilis Leuduger Fortmorel (Diat. de Ceylon PI. II, fig. 21).

N. blanda A. Schm. (Nordsee Diat. PL II, fig. 27).

N. latefasciata Grun. (in Cl. et Grun. Arct. Diat. PI. I, fig. 21\

KONGL. SV. VET. AKADEMIENS HANDLINGAK. BAND. 18. N:() 5. 13

N. subdivisa GrUN. (Nordsee Diat. fig, 20).
N. eonsimUis A. Schm. (1. c. p. 46).

N. cemula GuuN. (in A. Schm. Nordsee Diat. II, fig. 47).

N. superimposita A. Schm. (Nordsee Diat. II, fig. 34 and Diat. Atl. PI. 46,
fig. 61).
To these species are two undescribed forms nearly allied: N. Bruchii Grun.
and N. multiseriata Grun.

N. Bruchii Grun. (PI. III. fig. 35, ""7,) found on Tahiti, is in length 0,04 mm.
and in breadth 0,012 mm.

jV. multiseriata Grun. (PI. Ill, fig. 36, """/i) from Tongatabu, is in length 0,036.

Navicula. Section: Pseudo-amphiprora Cl.

I propose to include in this section a small number of Navicula-forms, which
are in some respects akin to Araphiprora and in other to Stauroneis. The valve on
both sides in the median line is divided by a keel into two portions. The central no-
dule is transversely dilated into a short stauros, reaching the above named keels. The
type of the section is:

Navicula arctica Cl.

In my paper On the arctic Diat. (Bih. till K. Sv. Vet. Ak. Handl. 1873, 1,
N:o 13, p. 16, PL III, fig. 13).

This fine species was first described and somewhat indifferently figured by Bailay
(Smiths. Contr. Vol. VII, p. 8. fig. 14 and 15, 1853) as Amphora stauroptera. Gre-
gory afterwards gave (in his Diat. of Clyde 1857, p. 34, PI. IV, fig. 59 c.) a very fine
figure of the species in (|uestion in S. V., but he regardes it as Anqjhiprora lepidoptera.
At the same time he describes the F. V. as Amph. obtusa (fig. 60 1. c). but Mr. Lager-
STEDT (Bih. till K. Sv. Vet. Ak. Handl. T. Ill, N:o 15, p. 46) has found that the two
figures (59 and 60) belong to the same species. As the names N. stauroptera and N.
obtusa have been used for other forms it will be most conveniant to name the species
N. arctica. A. Schmidt has figured the species in his Nordsee Diat. PL III, fig. 1 as
Amp)hiprora obtusa Greg. If the Nav. arctica O'Meaka (Micr. Journ. Vol. XIV, PL
VIII, fig. 1) belongs to this species I d'ont know.

The Nav. arctica lives in the northern part of the Atlantic. It has been issued
in Cl. et Moll. Diat. N:o 57.

21. Navicula jugata Cl.

Elegantly elliptic with parallel, indistinct, and punctate stria;, 10 in 0,01 mm.,
between the keels and the margins. The median portion of the valve, between the
keels, seems in very oblique light and with good objectives to be exceedingly finely
striate.

14 r. T. CLEVE, ON SOME NEW DIATOMS

Length 0,093 mm. Breadth 0,024 mm.

PI. Ill, fig. 38, '"7,.
Gallapagos Islands rare (Eugenie Exp.).

Grunow has found in the Campeche Bay gathering a closely allied form, Am-
phiprora Campechiana Grdn. (Arct. Diat. pag. 66), which has I2V2 strife in 0,01 mm.
and another species with 15 striae in 0,01 mm. and obtuse ends.

22. Navicula Pensacolce Cl. N. Sp.

Lanceolate, with undulate margins and prominent apices. Strife indistinct, pun-
ctate, 15 in 0,01 mm., parallel. The portion of the valve between the keels is very
indistinctly striate.

Length 0,054 mm. Breadth 0,015 mm.
PI. Ill, fig. 39, ^"""A-

Florida near the Harbour of Pensacola in a gathering sent by Mr. Febiger.

The following species is perhaps related to the species of this section :

23. Navicula Gallnpagensis Cl. N. Sp.

Panduriform, with cuneate ends. Stria? transverse, parallel, 15 in 0,01 mm., in-
distinctly punctate, reaching the median line and interrupted by a line or keel. The
median part of the valve around the median line is striate.

Length 0,067—0,092 mm. Breadth 0,025 mm.
PI. Ill, fig. 40, «'7i a. S. V. b. F. V.

Gallapagos Islands rare (Eugenie Exp.).

Stauroneis Ehb.

1. Stauroneis Balearica Cl. N. Sp.

Elongated, with acute ends. Stauros very short. Striie transverse, 26 in 0,01
mm., and longitudinal 23 in 0,01 mm., crossing each other in right angles.
Length 0,11 mm. Breadth 0,013 mm.

PI. Ill, fig. 41, a. ''V„ b- structure ^'""Vi-
Balearic Islets rare (F. Soderlund).

This species is nearly akin to St. Qnarnerensis (Grun. in litt.) from the Adriatic
Sea, which has also a short stauros and 18 longitudinal stria? in 0,01 mm.

2. Stauroneis sulcata Cl. N. Sp.

Linear, with cuneate ends, stauros reaching the margin. Structure: strong, lon-
gitudinal lines or furrows, parallel with the median line, and transverse parallel stria?,
21 in 0,01 mm.

KONGL. SV. VET. AKADEMIENS HANDLlNOAIi. HAND 18. N:0 5. 15

Length 0,088 — 0,109 imii. Breadth 0,008—0,00!) mm.

PI. Ill, Hg. 4(i, ^""7,.
Ralearie Islets rare (F. Sodehlund).

Among the Stauroneis forms, known to me, there are two, which have a similar
structure: St. Stodderi Lewis and 5/. Stodderi vai-. innupiis Gkun., both freshwater spe-
cies. St. sulcata is marine and has finer striae.

3. Stauroneis Africana Cl. N. S]i.

Valve very convex, hyaline, elongate. Stauros reaching the margins. Stria' hue,
23 in 0,01 mm., parallel, reaching the median line.

Length 0,05 mm. Breadth 0,01 mm.
PI. Ill, fig. 42, ^""V,, a. F.V., b. S.V.

Fresh, or very slightly brackish water, Zwathrops River, Port Elisabeth, South
Africa in a sample sent by Mr. W. Joshua (Cl. and Moll. Diat. N:o 196).

This form is nearly related to 6\ salina W. Sm., but has finer striae. The stria?
of S. salina are 17 in 0,01 mm.

4. Stauroneis pachycephala Cl. N. Sp.

Linear, gibbous in the middle and at the ends, which are broadly rounded and
capitate. Strite oblique, very fine, about 29 in 0,01 mm., reaching the median line.
Stauros reaching the margin. Median line straight. Terminal nodules turned in oppo-
site direction.

Length 0,055 mm. Breadth 0,009 mm.
PI. Ill, fig. 43, '°°7,-

Fresh or slightly brackish water, Baakens River, Port Elizabeth, Soutli Africa in
a sample sent by Mr. Joshua (Cl. et MOll. N:o 197).

This species comes nearest to St. desiderata Cl. (in Cl. et Grun. Arctische Diat.
PL III, fig. 58), which also has the terminal nodules turned in opposite direction, but
the outline of this species is different and its striae are almost parallel and much
coarser. Both belong to a section parallel with Grunows section Pseudopleurosigma
of Navicula.

5. Stauroneis {Pleurostauron) Sagitta Cl. N. S[).

Elongated, apiculate, to the outline resembling St. Smithii Grun. Ends with short
interior diaphrams as in Pleurostauron. Stria; oblique 21 in 0,01 mm. one or two in
the middle very strong.

Length 0,03—0,04 mm. Breadtli 0,006—0,01 mm.
PL III, fig. 45, '">'!,.

Fresh water, mouth of Tana Elf, Finmarken, collected bj' Prof. Th. M. Fries
(Cl. et Moll. Diat. N:o 261 not rare).

16 p. T. CLEVE. ON SOifE NEW DIATOMS.

This form has the appearance of S. Smithii Gron., but is larger and has coarser
stria' (being 28 in 0,01 mm. on S. Smithii) not so parallel as in 5. Smithii.

Schizostauron Grun.

1. Schizostauron Crudcula Grun.

Strite oblique, fine, 25 in 0,01 mm. Stauros bifid with very divergent branches,
reaching the margins.

Length 0,03 mm. Breadth 0,009 mm.
PL in, fig. 44, ^"""A-

Merrimac River U. St. on Chara, very rare in a gathering sent by Mr. 0. Nord-
STEDT. *)

Nitzschia W. Sm.

L Nitzschia ocellata Cl.

This species has already been described in Cl. et Grun. Arct. Diat. p. 80. The
frustule is panduriform; the keel central Avith 8 — 10 puncta in 0,01 mm. The strite
are fine, 22 in 0,01 mm. composed of small, elongate puncta. The strice are sharper
and more distant in the centre of the valve. The whole valve is covered with large
scattered puncta sometimes arranged in irregular, transverse lines.

Length 0,08 — 0,1 mm. Breadth of the frustule 0,027 mm. at the constriction
0,018 mm.

PL IV, fig. 47. '""Vi, a. valve, b. frustle.

Balearic Islets (Dr. Soderlund), Cl. et Moll. Diat. N:o 154 — 155 rare.

This species is placed by Grcnow in his section Pseudoamphiprora, very nearly
to Perrya Kitton.

2. Nitzschia prcelonga Cl.

This species has already been described in Cl. et Grun. Arct. Diat. p. 85. The
frustules are extremely long and slender, slightly arcuate, linear, with obliquely cuneate
ends. Keel almost central, with about 5 puncta in 0,01 mm. The stri* are strong,
16 in 0,01 mm.

Length 0,25 mm. Breadth 0,009 mm.
PI. IV, tig. 48, a. ""/x, b. """>u-

Balearic Islets not rare (Dr. F. Soderlund).

') In printing this paper I have been informed by Mr. Grunow that he has found the same form abun-
dantly in pools of the Rio Purus, Brazil, and that he has named it in Linuaean Society Journ. of May 1880
I consequently adopt his name.

KOXGL. SV. VET. AKADEMIEXS HAKDLIXGAR. BANT). 18. N:n 5. 17

Surirella Turpin.

1. Surirella Caldensis Cl. N. Sp.

Very long and slender, linear, with cuneate ends. Al* high. Canaliculi short,
numerous, 4 — 5 in 0.01 nun. Margin striate; striaj punctate 20 in 0,01 mm. F. V.
linear, not cuneate.

Length 0,108 mm. Breadth 0,013 mm.
PI. IV, fig. 50, """•/,.

Brazil. Caldas on Sphagnum (Dr. Hj. Mosen). Cl. et Moll. Diat. N:o 212,
common.

This species comes near to S. arcta A. Schm. Atl. PI. 23, fig. 23 — 24 from De-
merara, but its canaliculi are shorter and denser.

2. Surirella degenerans Cl. N. Sp.

Oblong, with very broad ends and slightly contracted middle. Margins striate.
CostiB obsolete, consisting only of the dilated portion. Area with some scattered mar-
kings and striae.

Length 0,09—0,072 mm. Breadth 0,037—0,046 mm.
PI. IV, fig. 51, ^«» ,.

Gallapagos Islands (Eugenie Exp.).

This form, which belongs to the variable section of S. lata, is related to S. laxa
Jaitisch.

3. Surirella formosa Cl. X. Sp.

Panduriform with large, rounded ends. Margin striate. Costa> abbreviate, with
the dilated portion comparatively large. The middle of the valve is occupied by a
narrow linear area, defined bv short striae.

Length 0,22 mm. Breadth 0,11 mm. at the constriction 0,07 mm.
PL IV, fig. 49, "\.

Gallapagos Islands extremely rare (Eugenie Exp.).

This very large and beautiful Surirella does not agree with any of the many
forms belonging to S. toa-section hitherto figured.

Canipylodiseus Ehb.

1. Canipylodiseus (Ecdesiatius var.?) peramplus Cl.

Very large, costae numerous 4 — 5 in 0,01 mm., equal in length, marginal. Area
large with a circle of puncta and with some stellate markings.

Diam. 0,12 — 0,16 mm.
PI. IV, fig. 53, ««7x.

Gallapagos Islands (Eugenie Exp.).

K. St. Vet. At lUndl Band. IS N:o 3. O

18 p. T. CLEVE, ON SOME NEW DIATOMS.

The C. Ecclesinnus Grev. (1857) is as Mr. Janisch correctly states the same as
C. fenef<tratus Grev., which is the entire frustule. Mr. Janisch proposed (1863) the
name C. Rabenhorstianus, but which should be changed for the older name of Gre-
viixe's. The type of this extremely variable species, especially abundant in the Ca-
ribbean are;i, has alternating longer and shorter costaj and an area not surrounded by
a circlet of puiicta. The form from Gallapagos Islands is therefore distinct, but, con-
sidering the great variability of the species, I am inclined to regard it only as a
variety.

The stellate markings on the disc are very variable, and in some specimens
Avanting.

2. Campylo discus Margaritarum Cl. N. Sp.

CostEE numerous, covering about "/s of the disc, interrupted by a fine line and
surrounding an elongate area, where some fragmentary punctate lines are visible as the
continuation of the costal.

Diam. 0,06 mm.

PI. IV, fig. 52, ^"Vi.

Pearl Islands rare (Eugenie Exp.).

In its general form this species resembles C. angularis Gkev., but is different.

Plagiogramma Grev.

1. Plagiogramma rutilarioides Cl. N. Sp.

Small, rhombic, more or less elongate, with two converging costjB around the
centre, but not near the ends. Structure: transverse punctate lines, 15 in 0,01 mm.
Margin with one or two sets of larger puncta, which probably are the bases of bristles.

Length 0,03—0,0425 mm. Breadth 0,01—0,013 mm.
PI. IV, fig. 54, >-7..

Port Jackson, Australia (Eugenie Exp.).

2. Plagiogramma spinosum Cl. N. Sp.

Valve narrow, constricted in the middle, then dilated, and again constricted.
Costae 2 strong, around the centre. Ends slightly capitate. Structure: puncta, arran-
ged in regular transverse rows, 10 in 0,01 mm. and in irregular longitudinal lines.
The margin of the frustule is furnished with a row of sliort setaj or bristles. The
ends of the valves have blank (not punctate), oval areas.

Length 0,08 mm. Breadth 0,01 mm.
PI. IV, fig. 55, ««7,.

The marginal setoa are visible when the frustule lies in an oblique position.

Gallapagos Islands rare (Eugenie Exp.).

This form has the same general outline as P. carihbteum Cl., P. lyratvm Grev
and P. Barbadense Grev. It is most nearly akin to the latter, but the ends are dissi-
mihar and the structure different.

KONGL. SV. VET. AKADEMIENS HANDLINGAK. BAND. 18. N:0 5. 19

RutilJiria Grev.

1. Rutilaria recens Cl. N. Sp.

Valve plane, elliptic or elonfjate with acute ends. It is covered with nuinerous
scattered puncta, which sometimes are arranged in irregular lines. Besides these there
are in the centre of the valve some more strongly marked puncta, and which seem to
belong to another stratum of the valve. The margin has a row of puncta, which are,
as may be seen in the F. V., short spines. In the F. V. the ends of the valve termi-
nate in short processes.

Length 0,037—0,11 mm. Breadth 0,02 mm.

PI. IV, fig. 57, a. """/j (an abnorm specimen having no puncta on a part of the
valve), b. ^°°/\ small specimen.

Gallapagos Islands (Eugenie Exp.).

The genus Rutilaria established by Dr- Greville, comprises only some few spe-
cies, all fossil. These are R. Epsilon Grev., rare in Monterey stone, R. superba (and
var.? ventricosa) Grev. and R. elUptica Grev. from Barbados. They all have the cu-
rious markings in the centre of the valve, which are elevations above the level of the
frustule, as is visible on the fig. 10, PI. XI, T. Micr. Soc. Vol. XIV. In our recent
species these markings are represented only by the strongly marked puncta. From
Geeville's fig. of the F. V. of R. ellijjtica and R. superba it is evident that the valve
is plane and that its apices are produced into processes, and farther that tlie margins
of the frustule are bounded with a row af setas, exactly as in our species.

The position of Rutilaria is somewhat uncertain. Greville has pointed out its
relationship to Nitzschia and Fragilariea\ Prof. Hamilton Smith places it among the
Melosiraj. It has however no real affinity with Nitzschia or Melosirai, but is very
nearly allied to the genus Cyiiiatosira Grun., of which the only known species C. Lo-
renziana Grun. has also marginal bristles. The Cymatosira is without doubt nearly
related to Dimerogramma.

Mr. KiTTON writes to me in a letter about a new species of Rutilaria from the
Californian deposits, Rut. obesum Grev. Mpt. The valve has 3 inflations, the central
being the largest; the apices are shortly cuneate; one third of the area is smooth, the
remainder distinctly covered with irregular markings. The central nodule consists of
a nebulous circular spot, u[)on which is placed a short spiral (?) ring. Margin distinctly
punctate. Mr. Kitton has seen about half a dozen specimens of this species, all
frustles, and in no case was he able to separate the valves. I crushing partially one
specimen in balsam, he observed that the nebulous central nodule was the base of a
siliceous isthmus, connecting the two valves.

3e SsEBtCSBh.

jS: iB^tirriB Tlr. ^i

liariPf^

^TL. TH T. _ii ^-. - 3i:.

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-ffC.

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''.'■ MJti/jw

31-

-mr — FT-

3Sl JX

JItlBdIliX.

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~'.T l?^^^T>f- T . T t .

ttM"

_ ■5r7'r-''j»«5a' ^oBOTsr Ii:. JT

jiKac

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tsasuBBoaamss. -^ Jkn

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JII-

22 p. T. CLEVE, ON SOME NEW DIATOMS.

Cyclotella Kutz.

1. Cyclotella Meneghiniana var. ? stelligera Cl. et Grun.

Disc with inar<>inal striae, about 14 in 0,01 nun., and with a central star of ra-
diating lines, alternately shorter and larger.
Diam. 0,02-2 mm.

PL V, fig. 63, '""Vi- ^- Specim. from New Zeeland; c. small specimen from
Lac de Gerardmer (Vosgues).
New Zeeland, Rotonia Lake, coll. by S. Berggren.

Another variety stellidifera Grun. is represented by the fig. h. and is characte-
rized by the granulate striaj.

Liradiscus Grev.

1. Liradiscus (?) Capensis Cl. N. Sp.

Circular, with a narrow, striate Tnargin (with 15 stria^. in 0,01 mm.). Disc co-
vered with curved and branching, but not anastomosing lines or markings, which do
not form a coherent network.

Diam. U,04 mm.

PI. V, fig. 61, '°7,.
Marine, Cape of Good Hope in a slide sent by Mr. F. Hauck.

Of the genus Liradiscus only four species are known, all fossil from Barbados
deposit. Our fornj, if it really belongs to Liradiscus, is the first known as recent. It
is doubtful if it not would be better to place it in Cyclotella, as it has s(jme relation-
ship to C. striata KiJTZ. or C. DaUasiana.

AuliscUS Bail.

1. Auliscus (?) insignis Cl. N. Sp.

Disc almost orbicular with 2 rounded, not truncate processes, and divided by a
large cruciform blank area in to four compartments. The comp;irtments have a very
singular structure and seem to be covered with irregular depressions, in the F. V. they
are elevated and the processes rounded.

Diam. 0,12 mm.

PI. V, fig. 64, a. *"%, S. V. b. '"/„ F. V.

Gallapagos Island extremely rare (Eugenie Exp.).

I am unacquainted with any Auliscus having the rounded processes of this glo-
rious species; it should perhaps be placed in the genus Cerataulus.

Annother remarkable species of Auliscus (A. Ralfsianus Grev.) hitherto known
only in a fossil state from the Barbados Deposit, occurs in the extremely interesting
Gallapagos material.

KOXGL. SV. VET. AKABEMIENS HANOI. INGAK. BAND. 18. N:(J 5. 23

Biddulpllia Gray.

1. Biddulpliid Moronensis (jL. N. Sp.

Valve in S. V. oval, stout, with two sti-diig transverse nista- and two laruc and
stout oval processes. Structure: large, irregularly scattered puncta on the valve and
tine dots arranged in irregular lines on the processes.

Length of the valve (^,12 mm. Breadth 0,07 mm.
PI. IV, fig. 56, '""/i-

Moron deposit in a slide from Mr. J. 1). Moller.

2. Biddulphia tenlaculifera Cl. N. Sp.

Valve elevate, covered with tolerably large puncta arranged irregular lines arouud
the centre of the valve. No costaj are visible. Processes elongate, club shaped.
Diam. of the valve 0,05 mm.

PI. V, fig. 67, «°7x.
Keeling Island (Eugenie Exp.).

3. Biddulphia Gallapagensis Cl. N. Sp.

S. V. broadly oval, almost orbicular, with two short stout processes. Structure:
pearly granules arranged in lines, radiating from the irregularly punctate centre to the
margin, about 12 — 13 in 0,01 mm.

Longest diameter 0,049 mm., shortest 0,04 mm.
PI. VI, fig. 74, '""Vi-

Gallapagos Islands (Eugenie Exp.).

This form belongs to the section of B. aurita, which contains a large number of
nearly allied forms, as B. Roperiana, B. Edwardii Febiger etc.

Triceratium Ehb.

1. Triceriitium {Hydrosera; Terpsinoe?) trifoliatuiii Cl. N. S[).

Valve plane, with concave sides and three 3-cuspidate angles, separated from the
valve by transverse lines (incomplete diaphragms). Surface covered with small puncta
arranged in irregular lines.

Diam. 0,045 mm. Distance between two apices 0,05 — 0,06 mm.
PI. VI, fig. 71, «»7i.

New Zeeland in fresh or slightly brackish water collected by Mr. S. Berggren
very rare.

This curious species is remarkable for its freshwater habit and seems to be most
nearly nlatcd to Hydrosera Wnllich from the Ganges, but it is entirely different.

24 v. T. CLEVE, ON SOME NEW DIATOMS.

2. Triceratium {Hydrosera; Terpsinoe) Javanicum Cl. N. Sp.

Valve plane, hexagonal, with three angles separated from the disc by transverse
lines (diaphragms) and alternating with three other angles, which are contigous with
the disc. One of the three latter angles has near the apex a small transvere fissure
corresponding to the appendages on Hydrosera triquetra Wallich. Structure irre-
gular 5 — 7-gonal cells, 4 — 5 in 0,01 mm., absent from the ends of the three first named
angles. F. W. Rectangular with longitudinal furrows, corresponding to the sinuses
beiween the angles.

Diara. 0,075 mm.

PI. VI, fig. 75, ""!,.

Java, Batavia in brackish water (Eugenie Exp.).

This form is so nearly related to Hydrosera triquetra Wallich Micr. Journ. VI,
p. 251, PL 13, fig. 1 — 6, that it perhaps might be more correctly regarded as a mere
variety.

3. Triceratium dubium Btw.

Micr. Journ. VII, p. 180, PI. 9, fig. 12 is the triangular form of T. hicorne Cl.
(Bih. t. K. Sv. Vet.-Ak Handl. PI. 5, fig. 30).

4. Triceratium Tripos Cl. N. Sp.

Outline in the S. V. almost orbicular or triangular with very broad and rounded
angles. Processes three near the angles. Structure a somewhat coarse and irregular
cellulation of hexagonal cells, about 5 in 0,01 mm. In the F. V. the valve is elevated,
sloping regularly from the apex to the margins. The three processes are strong and
and project somewhat obliquely.

Diam. of the valve 0,0525 mm.
PI. VI, fig. 72, '°Vi-

Gallapagos Islands (Eugenie Exp.).

5. Triceratium Anderssonii Cl. N. Sp.

This very rare and exceedingly fine species, of which I have found only one in-
complete specimen, is quadrangular with straight sides and rounded angles, upon which
are large truncate processes. The structure consists of branching veins, radiating from the
centre to the margins, and of tolerably coarse cellules, about 5 in 0,01 mm., of which
two rows fill the space between each pair of lines.

Greatest diameter 0,09 ram.
PI. VI, fig. 69, '"%.

Gallapagos Islands (Eugenie Exp.).

The structure of this remarkable species, which I have named in honour of the
late Prof. N. J. Andersson, is that of a Stictodiscus.

K(1N

(il.. SVKNSKA VET. AKADEMIENS HANDUNGAK. HAND. 18. N:0 5. 25

6. Triceratium la've Cl. N. Sp.

Triangular or quadratic, with straight sides and acute not produced angles. The
surface perfectly smooth, no structure being visible on balsam-specimens. In F. V.
the centre of the valve is elevated, and the angles are produced into processes, forming
right angles with the transverse diameter.

Distance between angles 0,02 — 0,0285 mm.
PI. VI, tig. 70, "7i, o. S. v., 6. F. V.

Gallapagos Islands (Eugenie Exp.).

7. Triceratium {productum Gkev. var.) Balearicum Cl. et Grun. (in Cl. et Moll. Diat.

N:o 154—155).

This form is closely allied to Amphitetras producta Greville and Triceratium An-
tillarum Cl. Its outline is 4 — 5 angular, with the angles produced into short processes.
The centre of the valve is elevated and by a depression separated from the margins.
The structure consists of rounded puncta arranged in lines, radiating from the centre
to the angles, about 5 in 0,01 mm.

Greatest diameter 0,06 — 0,08 mm.
PI. VI, fig. 73, '"7i.

Balearic Islets (Dr. F. SQderlund).

There can be not doubt that A. producta Grev. (Micr. Journ. II, p. 94, PL 9,
fig. 2) and T. Antillarum Cl. (Bih. till K. Sv. Vet.-Ak. Handl. Bd. V, N:o 8, PL V,
fig. 29) belong to the same species, which seems to be nearly allied also to Amphitetrax
elegnns Grev. from Monterey stone, in which form the depression between the centre
and the margins form an inscribed quadrate.

Allied to these forms seems to be Am. nobilis Grev. (Trans. Micr. Soc. 1865,
p. 105, PL IX, fig. 27) from the Red Sea. This species is however larger and seems
to be only the pentagonal form of Am. antediluviann. It occurs in Rabenhorst, Alg.
Eur. N:o 2264 from Livorno together with Am. antediluviana, and Mr. Kitton informs
me that he has found it in samples from Orkney Islands and Southampton; he also
remarks that the processes are much exaggerated in Grevilles figure. Another form
related to A. antediluviana is A. tessellata Shade. (T. M. S. 1854, p. 16, PL 1, fig. 11),
of which a variety with very coarse cellulation and large processes occurs in Moron
Deposit.

The Triceratium productum Grev. from Barbados Deposit is a quite different form
(see T. M. S. 1863, IX, p. 69, PL VIII, fig. 9).

8. Triceratium Gallapagense Cl. N. Sp.

Triangular, with acute angles, not provided with processes. Structure: distant
puncta, scattered over the disc of the valve, closer near the margins, where they form

K. Sv. Vct-Aknd. Hantll. Band. l.s. N:o 5. ■*

26 p. T. CLEVE, UN SOME NEW DIATOMS.

short rows, 5 in 0,01 inm. In the angles the puncta are much smaller and form fine
branching lines.

Distance between angles 0,0975 mm.
PI. VI, fig. 72, «"7i.

Gallapagos Islands rare (Eugenie Exp.).

9. Triceratiuin margaritiferum Cl. N. Sp.

Valve quadrangular with concave sides and rounded angles, without processes.
Surface probably plane. Structure tolerably coarse granules arranged near the margins
in short lines, smaller in the angles, rare and scattered in the middle.

Diam. 0,05 mm.

PI. VI, tig. 76, «"%.

Gallapagos Islands rare (Eugenie Exp.).

Chaetoceros Ehb.

1. Choitoceros Diclueta Ehb. = C. remotus Cl. et Grun.

This form has already been described in Cl. et Grun. Arct. Diat. p. 119 and is
to be found in most slides of Cl. et Moll. Diat. N:o 1 25.
PI. VI, fig. 77, '''I,.

Antarctic Ocean (Challenger Exp.).

Rhizosolenia Ehb.

1. Rhizosolenia {aiata var.?) gracillima Cl.

Extremely long and slender, measuring 0,5 — 0,7 mm. in length and only 0,006
mm. in breadth. The beaks are almost straight, provided with pocket-like impressions.
Tlie zig-zag markings on the connecting membrane are very indistinct. The frustule
is extremely hyaline, having no colour in dry state. No structure has been seen.
PI. VI, fig. 78, ^""7,.
West coast of Sweeden, Lysekil, freely floting on the surface of the sea (July
1877 by P. T. Cleve).

Another slender species, characterized by its coarse, of puncta composed strias,
Rli. Shrubsolii Cl. N. Sp., occurs in the Atlantic Ocean between Iceland and Green-
land. It was recently found in great abundance on the surface of the sea near the
island of Sheppey by Mr. Shrubsole.

Description of plates I VI.

Plate I.

Fig. 1. Mastogloia panduriformis Cl.

» 2. M. submargiuata Cl. et Grun.

» 3. Arapliora Berggreuii Cl.

» 4. Cymbella Brasiliana Cl.

» 5. C. Stodderi Cl.

» 6. Pleurosigma tortuosum Cl.

" 7. PL lanceolatum var. cuspidatum Cl.

» 8. PI. (Donkinia?) longissimum Cl.

» 9. Rboicosigma mediterraneum Cl.

» 10. Navioula (Fluminensis var.?) Ploridana Cl.

X 11. N. cruciata Cl.

» 12. N. Platessa Cl.

« 13. N. Groeulandica Cl.

» 14. N. Hennedyi var. Tahitensis Cl.

» 15. N. Hennedvi var. minuta Cl.

Plate II.

Fig.

16.
17
18
19
20
21
22
23
24
25
26
27

Navicula Eugenia? Cl.

N. rudis Cl.

N. Holmiensis Cl.

N. Hennedyi var. undulata Cl.

N. (excavata var.?) Angelorum Cl.

N. Febigerii Cl.

N. Clutheusis var. raiuuta Cl.

N. Cluthensis var. ? raaculifera Cl.

N. Fromenteroe Cl.

N. bicuspidata Cl. et Grun.

N. mesoleia Cl.

N. Hauclcii Cl

Fig. 28. Navicula Anderssonii Cl.

Plate m.

29. \. margiuulata Cl.

30. N. Powellii Lewis var. Gallapagensis Cl.

31. N. Wittii Grun. *

32. N. quadriserieta Cl. et Grun.

33. N. Castracanei Grun. *

34. N. Petitiana Grun. *

35. N. Bruchii Grun.*

*) Delineated by Mr. Grinow.

28 V- T. CLEVE, ON SOME NEW DIATOMS.

Fig. 36. Navicula raultiseriata Grdn. *

» 37. N. arnica Cl. ct Grun.

» 38. N. jugata ("l.

» 39. N. Peiisacola Cl.

» 40. N. Gallapagensis Cl.

» 41. Stauroneis Balearica Cl.

» 42. St. Afiicana Cl.

» 43. St. pachycephala Cl.

>i 44. Schizostauiou Cruciciila Grun.

» 45. Stauroneis Sagitta Cl.

» 46. St. sulcata Cl.

Plate IV.

Fig. 47. Nitzschia ocellata Cl.

» 48. N. praelouga Cl.

» 49. Surirella formosa Cl.

» 50. S. Caldensis Cl.

» 51. S. degeneraus Cl.

» 52. Carapj'lodiscus Margaritaium Cl.

» 53. C. (Ecclesianus var.?) peramplus Cl.

)) 54. Plagiogramraa rutilarioides Cl.

» 55. P. spinosum Cl.

» 56. Biddulphia Morouensis Cl.

» 57. Rutilaria recens Cl.

Plate V.

Actinella Guianensis Grun.

Asterolauipra Balearica Cl.

Coscinodiscus uudulatus Cl.

Liradiscus Capensis Cl.

Stephaiiodiscus (bellus var.?) Nov?e Zeelandiae Cl.

Cyclotella Meneghiuiana var. stelligera Cl. et Grun. a. from New Zeeland; b. from France;

c. stellulifera Grun.
Auliscus (?) insignis Cl.
Melosira (Podosira?) tuberculosa Cl.
Stictodiscus Novarse Cl.

Fig.

58.

»

59.

»

60.

M

61.

»

62.

»

63.

)>

64.

»

65.

l>

66.

l>

67.

Biddulpliia teutaculifera Ci..

Plate VI.

Fig. 68. Triceralium Tripos Cl.

» 69. T. Anderssouii Cl.

» 70. T. Ifeve Cl.

» 71. T. (Terpsinoe?) trifoliatum Cl.

" 72. T. Gallapagense Cl.

» 73. T. productum Grev. var. Balcaricum Cl. et Grun.

» 74. Biddulphia Gallapagensis Cl.

» 75. Triceratium (Terpsinoe?) .lavanicum Cl

" 76. T. luargaritiferum Cl.

» 77. Chietoccros Dichfeta Ehb.

» 78. Rhizosolenia (alata var.?) gracilliraa Cl.

--'ad HcUid

JCVetenskAtedHandlin^ar, BdlS.N: 5

■?ve etA-Grunowdel.

p. T. aeve del

-f-

KVetensk.Akad Handlingar Bdl8,N;5.

Pl.V.

50 h

PTaevedeL

KVetenslcAted Handliagar Bd.l8,N°. 5

PI VI

FT, Qeve del.

LE DIATOMISTE 11

par decouvrir apres des rechcrclns rciterees ; I'autre vase, au coiitraire, presontait sur hi legere
couche de bone dont son fond clail reconvert un riche depot de Diatomees. J'en conclus que,
laisses en repos pendant nn temps snl'fisant, les germes descendaient au fond de la cuve dont ils
s'elevaient a la nioindre secousse.

Dans les deux vases je trouvai quelqncs algues vertes unicellulaires, introduites par
rintermediaire de I'air.

Me servant de deux vases de la meine dimension dans lesquels je versai un demi-litre
d'eau puisee a la mSme source de ma provision, je resolus de varier mes experiences. Je fillrai
lentement et soigneusement, au travers de plusieurs doubles de papier a filtrer employe dans les
laboratoires, de I'eau que j'avais prealablement agitee. Le filtre commenca a laisser passer
90 gouttes a la minute, et il fallut 90 minutes pour filtrer un litre. Je mis de cote les filtres
employes et les plagai dans un pen d'eau pour les empeclier de secher. Comme a I'ordinaire,
environ six seraaines apres, cette eau fillree produisit une moisson abondante de Diatomees.

Avanl de conclure, je rapporterai une autre de mes experiences :

Apres avoir completement mele I'eau de la cuve qui etait dans la cave, on en prit un
litre, et comma auparavant cette eau fut fdtree et les fdtres employes mis de cote dans un peu
d'eau de mer. Je fis bouillir cette eau pendant 20 minutes et, une fois refroidie, je la divisai dans
deux vases, dans I'un desquels on lava tons les filtrc-s conserves; je plarai les deux vases sur la
meme fenetre et, au bout de six semaines, je les examinai au microscope. Le vase qui contenait
I'eau pure ne contenait aucune Diatomee, el il fallut des recherches reiterees pour trouver une
nwicule et un amphora dans celui ou les papiers avaient ete laves. Dans chacun des vases, tou-
tefois, se trouvaient des algues vertes unicellulaires apporlees evidemment par I'air. Les germes
de Diatomees etaient si petils qu'ils avaient pu passer presque entierement au travers dos filtres,
et je me deniandai si les germes qui avaient ete retenus n'etaient pas plus grands que ceux qui
avaient passe, de toute ftiQon,les Diatomeas ainsi produites, d'apres tous mes examens, etaient de
formes naturelles.

Je fus ainsi force d'admettre que j'avais affaire a des germes de Diatomees ou spores dont
la vitalite avait ete preservee dans I'obscurite pendant seize ans.

De la ma surprise, quand mon ami feu D>' Wolle, dans ses « Diatomacece of North Ame-
rica u, p. 13, tira de mon travail les deductions suivantes :

ct Quant a la longevite des Diatomees..., oa a trouvi qiielles peuvent survivre quoique
conservees pendant de longues periodes dans I'obscurite. »

« Independamment de leur reproduction par conjugation, il y a muliiplication par
division, et comme les Diatomees ne croissenlpas, ces divisions tendent a rendre les Diatomees qui
en resultent de plus en plus petites, jusqu'a ce qu'alteignunt une exiguite telle, observee chez les
NiTzscuiA, les Navicul.a. et les Amphora, elles peuvent passer, tout en eiant vivantes, au
trader's du papier a jlltrer. »

Je ne puis m'empecherdeconsiderer cette deduction comme une singulifere erreur; en un
mot, comme etant contradictoire aux trois faits qui me paraissent etre prouves par mes experiences.

12 LE DIATOMISTE

C etait la vitalite non du frustule ou plante, mais plulot du germe ou spore qui avail ete
conservee pendant une periodeauHsi longue et dans des circonstances si peu favorables ; car, avant
leur deve!oppement, je n'avais pu decouvrir avec I'aide du microscope aucune Diatomee vivante ;
et certainernent, si provenant d'un germe ou spore I'age de division d'une Diatomee doit etre pre-
cede d'une periode de croissance ou si Ton veul embryonnaire, assurer que les Nitzschia, les
Navicula et les Amphora peuvent passer a travers les pores du papier a filtrer me semble assez
surprenant.

Pendant seize ans, dans la Iranquillite et dans I'obscurite, la vilalite de ces germes a
sommeill^; comment done s'etonner que, lorsque revenant a une vie active, il se produise des
excentriciles dans leur developpement?Cequi m'etonne le plus c'est que, pour une forme irregu--
liere, il se trouve plus d'un millier d'individus conservant leur caractere parliculier; de plus,
quelques-uns d'entre eux avaient acquis un developpement si monstrueux qu'il depassait toute
description.

Quelques-unes de ces formes sont representees pi. II, fig. 1 a 22, qui est une reproduc-
tion des tableaux qui accompagnent mon etude publiee dans le Journal of the Netv-York Micros-
copical Society, Aecemher 1886, sous le litre: « Raising Diatoms in the Laboratory ».

Sur quelques especes nouvelles ou peu connues

Par M. P.-T. Cleve.

Navicula Gamma Cl.,ii. sp.

{PL I, fig- i, 2.)

Valve lanceolee a exlremites subroslrees. Longueur, 0,036 mm.; largeur, 0,014 mm.
Fissures terminales dela ligne mediane lournees en sens contraire. Aireaxiale indistincte. Airecen-
trale assez large, orbiculaire ou legSrement transversale. Stries au centre au nombre de 12, et
vers les extrdmites 13 en 0,01 mm., radianles jusqu'auxsommets, grossierement perlees. Perles,
14 en 0,01 mm., disposees en lignes horizonlales un peu ondulees.

Hab. : Eau d)uce ou un peu saumatre ; Amatitlan, Guatemala, lossile (rare).

Var. rectilineata CL, pi. I, ftg. 2. Longueur, 0,032 mm.; largeur, 0,014 mm. Stries,
16 en 0,001 mm., disposees en lignes longitudinales droites, 17 en 0,01 mm.

Hab.: Eau saumalre; Cameroon, Afriqne (rare).

Navioiila Epsiloii CI., ii. sp. (')
{PL I, fig. 3.)

Valve lanceolee a extremites rostrees. Longueur, 0,08 aO.Ol mm. ; largeur, 0,04 mm. Ligne
mediane a pores centraux dilates et a fissures terminales tournees en sens contraire. Aire axiale

(1) Le nombre des espfeces de Navicula est si considerable qu'ilnotis a falla employer I'alphabet grec pour
les nouvelles denominations.

LE DIATOMISTE 43

etroite, l^gSrement dilat(5e autour du nodule central. Siries, 10 en 0,01 mm., radiantes jusqu'aux
extremites, perlees. Perles dislancees ini^galement; vers les bords, 10 en 0,01 mm. ; a I'interieur,
oil parait se trouver une depression, 6 en 0,01 mm., disposees en series longitudinales ondulees.
Hab. : Marin, Chine, Japon.

Navii'iila Vlplia CI., n. sp.

{PL I, fig. 4.)

Valve largement lano^olee a extremites subrostrees obtuses. Longueur, 0,062 mm.;
largeur,0,03 mm.Lignemedianeapores cenlraux epaissis et a fissures lerminales tournees en sens
contraire. Stries, 7 en 0,01 mm., radiantes jusqu'aux extremites, ou elles sont unpeu plus serrees
(9 en 0,01 mm.), grossierement perlees. Perles, 8 en 0,01 mm. Stries medianes de longueur
inegale.

Hab.: Marin, Japon (Tempere).

i^iaviciila Ela CI., ii. sp.

(P. /, fig. 5.)

Valve hexagonale ou largement lineaire, extremites cuneiformes. Longueur, 0,044 mm.;
lai'geur, 0,010 mm. Aire axiale etroite, mais distincte, legerement dilalee au milieu. Stries, 10 au
centre, 50 vers les extremites en 0,01 mm., radiantes jusqu'aux extremites, perlees. Perles, 21
en 0,01 mm.

Hab. : Marin, Japon {Tempere), Mer Rouge.

Cette espece se rapproche beaucoup do la Nav. humerosa, mais elle en diOfere par sa laille plus
petite et ses siries plus serrees.

Navicula Ma'aiidriiia CI., ii. sp.
{PI. I, fig. 6.)

Valve elliptique, a extremites arrondies. Longueur, 0,045 a 0,065 mm.; largeur, 0,021
a 0,031 mm. Aire axiale etroite. Aire centrale orbiculaire assez grande. Stries, 19 a 21 en
0,001 mm., radiantes vers les extremites, composees de perles un peu allongees, disposees en series
longitudinales ondulees, 9 a 10 en 0,01 mm. Stries medianes de longueur inegale.

Hab.: Eau douce, Oregon (fossile).

Naviciila Delawareiisis Grim. list.
{PL I, fig. 7, 8.)

Valve elliptique lanceolee, a extremites subrostrees. Longueur, 0,85 a 0,1 mm.; largeur,
0,044 mm. Ligne mediane a pores cenlraux un peu ecart^s. Aire axiale etroite ; aire centrale
assez grande, arrondie. Stries, 14 a 15 en 0,01 mm., plus serrees vers les extremites, perlees.

i4 LE DIATOMISTE

Pedes, environ 11 en 0,01 mm., disposees en st§ries longitudinales ondulees. Stries medianes
de longueur inegale.

Hab.: Eaux saumatres, Connecticut {Tempere), Embouchure du Delaware.

Celte espece se rapproche beauotup de la Nav. pusilla W. Sm., mais elle est beaucoup plus
large.

i\avicula Deraerara (iriiu. Jls(.

(PI. I, fig. 9.)

Valve largement lanc^olee, a extremites aigues ou subobtuses. Longueur, 0,046 a
0,085 mm.; largeur, 0,017 a 0,03 mm. Aire axiale tr§s etroite ou presque indistincte. Aire cen-
trale assez grande, irreguliere; une ou plusieurs grandes perles du cote du nodule. Fissures ter-
minales de la ligne mediane tourn^es en sens contraire. Stries, 15 a 17 en 0,01 mm. ; un peu plus
serrees vers les extremites, radiantes, ponctuees. Perles, 19 en 0,01 mm. Stries medianes de lon-
gueur inegale ; stries terminates paralleles .

Hab. : Eau douce, Demerara River, Surinam (Coll. Kinker).

INaviciila Delia CI., ii. sp.
{PL I, fig. iO.)

A'alve elliptique, a extremites rostrees. Longueur, 0,032 mm.; largeur, 0,016 mm. Aire
axiale etroite ; aire centrale assez large, orbiculaire. Stries, 12 en 0,001 mm., radiantes jusqu'aux
extremites, grossierement perlees. Perles, 12 en 0,01 mm,, egalement espacees. Stries medianes de
longueur inegale.

Hab. : Marin, Poinle de Galle, Ceylan (Coll. Weissflog).

NavJcula Tail CI., ii. sp.
{PL I, fig. Ii.)

Valve allongee, legerement bicontractee, a extremites cuneiformes. Longueur, 0,037 mm.;
largeur, 0,01 mm. Aire axiale etroite. Aire centrale distincte orbiculaire. Stries, 20 en 0,01 mm.,
radiantes jusqu'aux extremites ; stries medianes de longueur inegale.

Hab.: Eau douce, Demerara River.

Cette espece apparlieut, ainsi que la Nav. limicola, a la section Xavicula lielerosliclia CI.

JVaviciila limicola CI., ii. sp.

{PL 1 Jig. 12.)

Valve elliptique, a extremites arrondies. Longueur, 0,0i0 min. ; largeur, 0,0017 mm.
Aire axiale etroite ; aire centrale assez large, orbicLilaire. Stries, environ 25 en 0,01 mm., legere-

LE DIATOMISTE 45

ment arquees et radianles jusqu'auxextremites;aponctuation fine, m.iis distincte ; stries medianes
a ponctuation plus grossc vers I'aire centrale et de longueur inogale.
Hab. : Eau saumalre, Cameroon, AlVique (rare).

Cetle espcce apparlient a la petite section Navicula heterosticha qui renferme, en outre, Navicula
cocconeiformis Greg et Navic. scutifornm Gnm.

Navicula Pi <!!., ii. sp.
{PL /, fig. i3.)

Valve allongee, rhomboidale, a extremites obluses. Long., 0,08 mm.; larg., 0,022 mm.
Aire axiale indistincte; aire centrale petite. Fissures terminales de la ligne mediane tournees
dans le meme sens. Stries, il en 0,04 mm., plus serrees vers les extremites (42 en 0,01 mm.)
presque paralleles, perlees. Perles, 42 en 0,04 mm. disposees en series longitudinales ondulees.

Hab. : Mann, Chine (Coll. Van Heurck).

Cette espece se rapproche beaucoup des Nav. Doljensis et Nav. Brunii Pant.

Navicula Grovei CI., n. sp.

(PI. /, fig. U.)

Valve legerement lanceolee, a extremites obluses. Longueur, 0,00 min.; largeur,
0,03 mm. Aire axiale etroite; aire centrale large, dilatee. Fissures terminales tournees dans le
meme sens. Stries, 4G en 0,04 mm., radiantes jusqu'aux extremites, perlees. Perles egalement
espacees, 45 en 0,04 mm. Quelques stries medianes sont plus courtes que les autres.
Hab.: Marin, Oamaru, Nouvelle-Zelande (fossile).

)lasto|^loia riniosa CI., n. sp.

\pi.I,fig.i5.)

Valve rhomboidale, lanceolee, a extremites rostrees. Longueur, 0,037 mm. ; largeur,
0,013 mm. Ligne mediane ondulee. Aire axiale etroite, mais distincte. Logettes, 10 en 0,04 mm.,
rectangulaires, formant une bande atteignant les apiculi. Stries non perlees, 44 en 0,04 mm.,
legerement radices, convergentes aux extremites, traversees par une aire laterale etroite.
Hab. : Marin, Bahamas (Grove Coll.).

.Masloglola obesa CI.
(P/. /, /ig. i6.)

Valve largement lanceolee, acuminee. Longueur, 0,04 mm.; largeur 0,024 mm. Ligne
mediane legerement ondulee. Aire axiale tres Etroite ; aire centrale quadrangulaire s'unissant aux
aires laterales arquees. Logeltes, 6 en 0,04 mm., quadrangulaires, formant une bande attei-
gnant les extremites. Stries, 42 en 0,04 mm., composees de grosses perles espacees. Entre les
stries marginales et les aires arquees, se trouvent quelques series de perles allongees.

Hab. : Marin, Java.

16 LE DIATOMISTE

Mastogloia balianieosis, CI., n. sp.
{PL I, fig. il.)

Valve elliptique ou subrhomboidale. Longueur, 0,045 mm. ; largeur, 0,022 mm. Ligne
mediane non ondulte. Aires axiale et centrale indistinctes. Logettes, 12 en 0,01 mm., egales,
reclangulaires, formant une bande marginale atteignanl les extremites. Stries, 43 en 0,01 mm.,
composees de grosses perles allongees, disposees en lignes longitudinales ou irr^gulierement
decussees.

Hab. : lies Bahamas (Coll. Grove).

Cette espece ressemble parses caracleres au Mastoglia affirmata (Leud. — Foi'tniorel)Cl., mais elle
est beaucoup plus petite.

Mastogloia ciispidata CI., ii. sp.

{PL /, fig. iS.)

Valve elliptique, apiculee. Longueur, 0,026 mm.; largeur, 0,01 mm. Ligne mediane
forlement ondulee. Aires axiale et centrale indistinctes. Logettes, 6 en 0,01 mm., quadrangulaires,
formant une bande marginale n'atteignant pas les extremites. Stries, 25 en 0,01 mm., paralleles,
indistinctement ponctuees.

Hab. : Marin, lies Bahamas (Coll. Grove).

Cetle espece ressetnble beaucoup au M. minuta Grev, donl elle difTere par sa striation beaucoup
plus fine.

Uastogioia aiitiqiia CI., ii. sp.

{PL I, fig. iO.)

Valve rhomboidale. Longueur, 0,08 mm.; largeur, 0,03 mm. Ligne mediane legerement
ondulee. Aire axiale etroite, lanct§olee. Logettes, 6 en 0,01 mm., egales, quadrangulaires, reunies
en une bande inlra-marginale s'arretant a une cerlaine distance des extremites. Stries, 18 en
0,01 mai., paralleles, legerement radices vers les extremites. Perles, 18 en 0,01 mm., disposees
en series longitudinales ondulees.

Hab. : Karand, Hongrie, fossile (Coll. Deby).

Maslogloia (Iclicatiila CI., n. sp.

{PL I, fig. 30.)

Valve lanceolee, acuminee. Longueur, 0,037 mm.; largeur, 0,014 mm. Ligne mediane
faiblement ondulee. Aires axiale et centrale indistinctes. Logettes, 6 en 0,01 mm., egales, formant
une bande marginale atteignant presque les extremites. Stries, 21 en 0,01 mm., paralleles, com-
posees de petites perles disposees en series decussees.

Hab. : lies Bahamas (Coll. Grove).

Le DiATOMiSTE , Vol. II.

Planche II

Les figures de cette plunche ont ete dessinees avec soia d'apres les formes observ6es dans une pre-
paration faile avec la culture G de la premiere s6rie d'essais; elles sont grossies 1,000 fois, excepts figures
2'^, 2b, 2'' et 8* qui sont a un grossissement de 800 diametres.
Fig. 1 Forme rare dans la culture.

— 2 Forme assez commune et que Ton retrouve au centre des series representees par les figures

20, 21 et 22.

— 3 a 17 representent les monstruosites dont la figure 3 est la forme typique.

— 15, 16 et 17 sont des formes anormales particulieres, dont la figure 17, qui s'eloigne de la figure 3,

semble etre la forme normale.

— 12 Groupe de petits amphora grossis 350 fois.

— 19 Serie provenant de la forme 2'-.

— 20, 21 et 22. Series ayant pour point de depart la forme representee figure 2.

Le DiATOMiSTE Vol. II

Planche I

Fig. ^■2 NaviculaGammaCL, n. sp. Gross. 1000 Page 12

— 3 Navicula Epsilon CI., n. sp. -

— 4 Navicula Alpha CI., n. sp.

— 5 Navicula Eta CL, n. sp.
- ti Navicula Moeaudrina CL, n. sp.

— 7 Navicula Delawarensis GfiUN'., mst. -
^8 — _ — ( partie de la valve) -

— 9 Navicula Demerara Grun Mst.

— 10 Navicula Delta CI., n. sp. -

— H Navicula Tau CI., n. sp.

— 12 Navicula limicola CI., n. sp. -

— 13 Navicula Pi CI. . n. sp.

— 14 Navicula Grovei CI. , !i. sp.

— 13 Mastoy,-loia rimosa CI., n. sp. —

— 16 -Mastogloia obesa 01.. n. sp. —

— 1" Mastogloia bahamensis CI., n. sp.

— l.S Mastogloia cuspidala CI., n. sp. -

— 19 Mastogloia antiqua CI. , n. sp. -

— 20 Mastogloia delicatula CI.. II. sp. -

500

—

12

iOOO

—

13

1000

—

13

1000

—

13

oOO

—

13

1000

—

13

1000

—

14

1000

—

14

1000

—

14

1000

—

15

1000

—

1j

1000

—

l.j

IOOO

—

I. J

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—

l.j

1000

—

10

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—

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1000

—

it;

1000

—

IG

LE DIATOM I STE

PLANCHE I

VOL. II.

Phototypic F. Th6voz & C". Gcnvuc

LE DIATOMISTE

VOL. II

PLANCHE III

t'l,olornHi»j,ui.l,U- Cti.iit d hm;i.,H. - I'-i

Le DiATOMlSTE

Vol. II

Planche III

Fig.

9

10

11

12

13

14

13

10

17

18

19

20

21

^^

Mastogloia floridea Gl., n. ?p.
Mastogloia Pisckulus CI., n. sp.
Gyrosigma Teraperei CI., n. sp.
Gomphoneraa Astuarii Gl., n. sp.
N;ivic'ula Theta CI., n. sp.
Navicula Omega Gl., n. sp.
Amphora Scabriuscula Gl. el Grove, n. sp.
Amphora elegans Pcragallo, n. sp. (a).

- - - (b).

- - - (c).
Achnanthes(AchnanthidiumGl.)MargaritaceumGI.,n.

Achnanlhes (Actinoneis Gl.) heteromorpha Grun

Achnanlhes (Actinoneis Cl.)inopinata Gl.

Achnanlhes (Heteroneis CI.) Vaszaryi Gl.

Achnanlhes (Heleroneis Gl.) Americana GL, n. sp.

Achnanlhes (Heleroneis Gl.) Lilljeborgii Grun.

Gocconeis (Heteroneis Gl.) Lagerheimii GL, n. sp.

Gross.

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LE DIATOMISTE 55

Sur quelques especes nouvelles ou peu connues

{Suite.)
Par P. T. Cleve.

Mastogloia floridca CI., ii. sp.

{PL. HI, fig. /.)

Valve elliptique, rostree. Longueur, 0,043 mm. ; largeur, 0,015 mm. Ligne mediane
droile. Aire axiale indislincle ; aire centrale petite, arrondie. Logettes inegales, les deux ou qualre
medianes beaucoup plus larges que les aulres, 8 ou 9 en 0,01 mm., formant une bande elroite el
marginale s'etendant presque aux extremites. Stries, 15 en 0,01 mm. legSrement radia/ites au
milieu de la valve, paralleles vers les extremites, ponctuees, les points (14 en 0,01 mm.) disposes
en series longitudinales.

Hab. : Marin, Pensacola (Grove Coll.).

Nastoj^loin pisciciiliis CI., u. sp.

(PL III, fig. 2.)

Valve lanceolee,subacuminee. Longueur, 0,05 mm. ; largeur, 0,015 mm. Ligne mediane
ondul^e. Aire axiale indistincte ; aire centrale petite, orbiculaire. Logettes, 4 eu 0,01 mm., egales,
quadrangulaires, formant une bande marginale n'atteignant pas les extremites. Stries, 21 en
0,01 mm., presque paralleles, un peu radiantes aux sommels,fmement ponctuees, les ponctuations
disposees en series longitudinales. A quelque distance de la ligne mediane, les stries sont traver-
seespar une ligne longitudinale; entre celle-ci et la ligne mediane elles sont moins marquees.

Hab. : Marin, Pensacola (Grove Coll.)

Gjrosigiiin Toiiiperoi CI., n. sp.

{PL III, fuj. 3.)

Valve lineaire droite, a extremites obliquement arrondies. Longueur, 0,14 mm.; largeur
0,014 mm. Ligne mediane centrale droite, courbee aux extremites. Stries longitudinales, 30
transversales, 27 en 0,01 mm.

Hab. : Eaux saumatres, Connecticut.

Je propose dediviseren deux genres I'ancien genre f/e^ros/f/z^c!. J'appellerai/'/efwosf^ma, les formes
a slriation oblique, el Gyrosigma celles a striatiou droite, nom plus ancien etdeja donne par Hassall.

Gomplioineiia a'stuarii CI., n. sp.

{PL Iff, fig. 4.)

Valve presque lineaire, a extremites arrondies. Longueur, 0,02 a 0,028 mm.; largeur, 0,002
a 0,003 mm. Aire axiale nulle, aire centrale, un pseudo-stauros transversal et assez large, sans
pedes isolees. Les stries qui bordent I'aire centrale sont radiantes, les autres paralleles, 20 en
0,01 mm. A la base de la valve inierieure se trouve un diaphragme distinct.

Hab. : Sable de Hastings, Angleterre (Coll. Grove).

56 LE DUTOMISTE

IViivicula Tlieta CI., ii. sp.

(PL 111, fig. 5.)

Valve oUiptique. Longueur, 0,055, mm. ; largeur, 0,028 mm. Aire axiale etroite,
lineaire ; aire cenlrale arrondie, a bord fimbrie. Stries, au ce.itre de la valve ou elles sont de
longueur inegale, 20 en 0,01 mm. ; vers les extremiLes, 25 en 0,01 mm., radiantes, dans les
sommets memes presque poralleles, fiiiement ponctuees, les points (21 en 0,01 mm.) formant
des stries arquees paralleles aux bords de la valve.

Hab. : Kau douce, Oregon (fossile).

Celte espece apparlient a la section Navkulx heterosiichx el se rapproche de la Nav. inmcola
CL, et de laiVoi'. coccotieiformis Gveg.

I\aYiciilaOmegaCI.,ii. sp.

(P/. [II, firj. G.)

"Valve elliptique, subroslree. Longueur, 0,026 a 0,035 mm. ; largeur, 0,015 a 0,018 mm.
Ligne mediane aboutissant ;\ quelque distance du bord de la valve. Aire axiale indistincte; aire
centrale petite, arrondie. Stries, 17 en 0,01 mm., legeremenl radiantes jusqu'aux sommets,
distinclementperlees.Perles, 17 en 0,01 mm., arrangees en ligneslongitudinales presque droites.

Hab. : Marin, Etretal (Temp, et Perag. Type no 400).

Cetle espece, nommee dans les types de Temp, et de Perag. Nav. marina, en est bien distincte par
I'arrangement de ses perles, par sa ligne mediane abregee ainsi que par ses dimensions.

Aiiipliora scabriiisciila CI. el Grove, ii. sp.

{PL III, fig. 7.)

Valve lineaire obtuse. Longueur, 0, 057 mm. ; largeur, 0,01 mm. Cote dorsal sans ligne
longitudinale,maisa aire assez large. Structure: alveoles assez larges,disposees en lignes radiantes,
10 en 0,01 mm., et finement striees transversaleinent. Cote ventral entierement couverl de
stries robustes, 10 en 0,01 mm.

Hab. : Marin, Detroit de Macassar (Coll. Grove).

Celte espece offre un inlerel considerable, en cequesa slruclure esl exaclemenl celle du genre Tra-
cltijiicis (Navicula) aspera Elir. Elle ressemble en ceci a i'.A.iiipfior.i Clevei Gruii.

Aiupliuia elcgaus Perag., n. sp.

{PL III fig 19.)

Frustule allonge, (^troit, a bords tres peu convexes et k extremites tronquees. Longueur,
0,09 mm.; largeur, 0, 015 mm. Zone connective simple. Valve etroite, lineaire, aigue. Longueur,
0,08 mm. ; largeur, 0,01 mm. Nodule central dilate en stauros. Cote dorsal sans ligne longitu-
dinale et sans espaces hyalins. Cote ventral ayant la meme structure que le c6t6 central. Struc-
ture : perles fines disposees en stries transversales, 22 en 0,01 mm., el en stries droites longitudi-
nales, 25 en 0,01 mm.

LE DIATOMISTE 57

A. elegans (Coll. Tempore et Peragallo, no 414). .
Hab. : Marin, Cabours.

G'est une cspece remarquable el fort interessante, elant une forme asynielrique du type de la
Aavkula (Endostauron) crucitjera W. Sm.

Acliiiaiillies (Acliiiaiilidimn f\.) Miu'narilanim CI., ii. sp.

[PL III, fig. 9-10.)

Lanceolee, a extremil^s legerement allongees. Longueur, 0,05 a 0,00 mm. ; largeur,
0,02 mm. Valve sxiperieure a aire axiale etroite. Stries legSrement radiantes, 10 (au centre) a 13
(aux extremites), composees do pedes distinctes, disposees en lignes droites longitudinales, 15 en
0,01 mm. Valve injerieure sans aire axiale et a aire certrale petite et orbicuiaire. Stries sembla-
bles ci celles de la valve superieure.

Hab. : Marin. Pearl Islands !

Cette remarquable espece rappelle beaucoup, par sa valve superieure, le Raplioneis ampkiceros.
C'est une forme tout a fait a part(l).

Acliiianllics (Aelinonois CI.) Iioteroinorplia Grim

[PI. Ill, fig. U-12.)

Rhomboidale ou lanceolee. Longueur, 0,04GaO,08 mm.; largeur, 0,0"2 a 0,055 mm. Valve
superieure a aire axiale etroite, ayant vers I'un des bords une marque en fer de chevai. Cotes, 8 a
10 on 0,01 mm., legerement radiantes, indistinctement (d'apres Grunow finement) ponctuees.
Valve inferieure a aire lanceolee assez large. Stries, 7 (au milieu) a 9 (vers les extremites) en
0,01 mm., fortement radiantes jusqu'aux sommets.

A. Heleromorpha Grun, Arctische Diatomeen, p. 23.

Hab. : Eau douce, Demerara River.

Aclinanllies (Acdiioiiois CI.) inopiiiala CI.

(PI. Ill, fig. 13-14.)

Rhomboidale, aiguii. Longueur, 0,027 mm. ; largeur, 0,009 mm. Valve superieure a aire
axiale tres etroite, portant une marque en fer de chevai sur I'un des bords. Cotes, 12 en
0,01 mm., presque paralleles, non ponctuees. Valve inferieure a aire axiale etroite. Aire
centrale quadrangulaire reunie aux aires laterales lunaires. Stries, 14 en 0,01 mm., radiantes.

Hab. : Marin, Depot de Baldjik (fort rare).

Aclinanllies (HeleroniMS CI.) Vaszani Pant., var. Oregonica CI.

[PL III, fig. 15-16.)
FormctypiqueA.VASZ.\RYi Pant. — Rhomboidale, aigue. Longueur, 0,06 mm,; largeur,

(i) Je propose de reunir les Cocconeis et les Aciinantiies el de former de nouveaux genres des
formes qui sont liees par des caracteres essentiels, sous les noms dWctinoneis, (THetei'nneis, d'Achnanthes,
d'Achnanlhidium, etc.

58 LE DIATOMISTE

0 03 mm. Valve superieiire inconnue. Valve inferieure a aire axiale tres ^troile et a aire cen-
trals assez large, dilatee el fimbriee vers les bords de la valve. Stries medianes de longueur
inegale, 13 en 0,01 mm., presque paralleles; les autres slries fortement radianles jusqu'aux
extremites, environ 20 en 0,01 mm. (d'apr^s la figure de M. Pantocsek).

Navicida Vaszaryl Pant., Dial. foss. Ungarns III, p!. XVI, fig. "239.

Hab. : Eau douce (?), Nyermegy (Pant.).

Var. Oregonica CI. — Lanceolee, a extremites subrostrees,obtuses. Longueur, 0,03 mm.;
largeur, 0,013 mm. Valve superieure a aire axiale lanceolee, mesurant un tiers de la largeur de
la valve et portant une marque en fer de cheval sur I'un des bords, munis de cotes. Cotes lege-
rement radiantes, 16 en 0,01 mm., alternant avec des pedes trfes fines disposees en stries
obliques, environ 30 en 0,01 mm. Valve inferieure semblable au type. Stries medianes, 18 en
0,01 mm.; les autres, 2(5 en 0,01 mm., plus serrees vers les extremites.

Hab. : Eau douce, Oregon (fossile).

Cest une espece fort interessante dont la valve inferieure offre beaucoup de ressemblance avec celle
de VAcknanthes (Actinoneis CI.) damca Flogel. La difference autre la Navicida Vaszaryi Pant, el la valve
inferieure de la forme de I'Oregon, est de si peu d'iaiportance que je n'ai pas cru devoir la considerer
comme une espece dislincte. {A suivre).

Note

sur rexamen comparatif des coupes faites sur les ciments calcaires diatomiferes

de Mors (Jutland), et de Sendai (Japon)

Par J. Tempere.

Dans leur interessant travail public dans le tome VIII des Annales de la Societe Beige de
Microscopie, sur la composition des ciments calcaires du Jutland et sur la structure des Diatomees
qu'ils contiennent, MM. W. Prinz et E. Van Ermengen ont fait judicieusement remarquer que ces
depots s'etaient formes dans des conditions toutes speciales de tranquillile, indiquees par la posi-
tion qu'occupetit les Diatomees qu'on y trouve. En effet, les valves et les frustules y observent
toujours une direction horizontale,^e qui permet, par une bonne orientation verticale, d'obtenir
des coupes parfaitement nettes et r^giiliferes de ces Diatomees, laissant voir ainsi lr6s nettement
leur structure interne, etcela bien mieux que dans I'ingenieux procede de Flogel, oil les parties
constituantes peuvent malheureusement trop facilement se deplacer. Cette orientation est facilitee
par la presence, dans certains echantillons, de couches variant d'epaisseur et de couleur, mais
toutes parfaitement paralleles I'une a I'autre, et indiquant par cela meme I'exacte direction de
la coupe. Les fig. 1-4 de la planche IV representent des coupes faites dans les deux directions, et
feront mieux comprendre que loute description ce que je viens de signaler.

Les fig. 5-6 sont des reproductions de coupes faites sur le calcaire de Sendai (Japon). Ici,

PSEUDO-RAPHIDEES

Grammatophora ferpeiitina; F.lir.
Rhabdonema arcuatuin, Kiitz.
Surirella strialula, Turp.
Nitzschia sif^ma, W. Sni.
— marginulata, Griin.

LE DIATOMISTE 143

Campylodiscus Ralfsii, W. Sm.
— Tliuretii, Breb.

CRYPTO-RAPHIDEES

Melosira sulcata, Kiitz.
Actinoptychus undulatus, Ehr.
Coscinodiscus minor, Ehr.

Sur quelques esp6ces nouvelles ou peu connues

Par M. P.-T. Cleve

(Descriptions faisant suite a celles donnees page 58)

Aclinantlies (Hcteroneis) lilljeborgii CI., n. sp.
(PL III, fig. i9-W)
Lanceolee, obtuse. Longueur, 0,017 a 0,046 mm. Largeur, 0,008 a 0,01 mm. — Valve
superieure assez robuste, h aire axiale lanceolee, mesurant 1/3 de la largeur de la valve, portant
de grosses granulatioas eparses. Cotes 8 ou 9 en 0,01 mm., 16gerement radices, non ponctuees.
— Valve inferieure mince, a aire axiale etroite. Slries 12 en 0,01 mm., radiees au centre, dont
quelques-unes plus courtes entre les autres, paralleles vers les extr^mites.

A. Lilljeborgii Griin. Bot. Centralbl. 1881, p. 62. — Cleve Marine Diatoms, nos 101, 102,

311.

Hab. : Marin, Grip en Norvege, He de Brehat (C6tes-du-Nord), Griinow.

Aclinanlhcs (lleteroiieis) Americana CI., n. sp.

(PL in, fig. 17-18.)

Longuement elliptique, a extremites subtronquees. Longueur 0,013 mm, Largeur
0,006 mm. — Valve superieure a airelarge,lanceolee. Stries16en0,01 mm., interrompues sur un
des cotes. — Valve inferieure a air axiale, lanceolee. Stries 17 en 0,01 mm., radiees et se rac-
courcissant vers le milieu de la valve.

Hab. : Eau douce : Crane PonJ (Amerique du Nord).

Cocconeis (Heleroneis) Lagerheiniii CI., n. sp.

{PI. in, fig. 21-22.)

Elliptique. Longueur 0,02 a 0,028 mm. Largeur, 0,01 a 0,015 mm. — Valve supe-
rieure robuste a aire axiale, lanceolee, ornee au centre de deux rangees de grosses pedes.
Stries non ponctuees, les deux medianes de I'un des cotes formant par leur reunion un fer a
chevaL — Valve inferieure mince, a ligne medians droite. Aire centrale se combinant aux aires
laterales, assez larges el lunaires. Slries lines 25 en 0,01 mm.

Hab. : Eau douce : Equaleur (region tropicale).

144 LE DIATOMISTE

N.'ivinila llerrmaiiii Rciclielt, n. sp.

(PL IX, fig 1.)

Valve lanceolee, souvent rostree, k exlremites obtuses. Longueur, 0,09 mm. Largeur,
0,023 mm. Ligne mediane droite. Aire axiale distincte, lineaire, un peu dilatee vers le nodule
central. Stries 12 (au milieu) a 14 (aux exlremites) en 0,01 mm., legerement radices, ~presque
paralleles aux sommets, composees de pedes distinctes, au milieu 10, en 0,01 mm. , dansles stries
terminales 12 en 0,01 mm., disposees en rangees longitudinales ondulees. Au bord meme de la
valve, les stries sont interrompues par une depression etroite et canaliculaire.
Hab. : Eau douce : Breilen Busch en Boheme, fossile (lertiaire).

Cette espece se troUve assez abondanle dans le depot de Breilen Busch, examine par M. Reichelt
(Berisclile der Naturforschenden Gesellschaft zn Leipzig, 1892-93, page C7), depot interessant qui conlient,
entre autresespeces nouvelles, lebeau Gompliopleuranob^lisKeiQXiM.he. noni de N. Hervmami a ete donne
par M. Reichelt sur une preparation, qu'il a bien voulu me communiquer. C'est une espece fort remar-
quable a cause de la ligne du bord de la valve, caractere peu apparent sur les exemplaires parfaits, mais
bien visible sur les fragments, qui se trouvent en abondance dans le dep6t. II n'y a pas, que je sache, des

Navicula d'une structure pareille, si ce n'est le Navicula decora el le Nav. interlineata Grove and Sturt, tous

les deux marins d'Oamaru.

I\avicula giialeinaleiisis CI. el (irove, n. sp.

[PL IX, fig. 2.)

Valve allongee, lanceolee, a soinmets obtus. Longueur, 0,115 mm. Largeur, 0,018 mm.
Ligne mediane droite, bordee d'une aire axiale etroite; ses fissures terminales courbees dans la
meme direction. Stries transversales et longitudinales ; les stries transversales paralleles, 11 en
0,01 mm. ; les stries longitudinales, 23 en 0,01 mm.

Hab. : Eau douce: Guatemala, fossile (coll. Grove).

Celle espece apparlienl a la section que j'ap|)elle Nav. orlhostichx, qui est caracterisee par des stries
transversales et longitudinales droites, se croisant a angle droit. C'est la plus rapprochee du Nav. cuspi-
ddta, qui en differe par la forme et par une strialion plus fine.

Kaviciila delicaliila CI., n. sp.

(PL IX, fcg. 3.)

Valve etroite, presque lineaire, un peu elargie au milieu, a sommets capites. Longueur
0,065 mm. Largeur, 0,005 mm. Ligne mediane a pores terminaux a quelque distance de I'exlre-
mit6. Strialion non observee.

Hab. : Marin: Fiskebaekskil, BobuslAn, Suede.

Cette espece ressemble, par sa forme, au Nav. scopulorum, mais elle est beaucoup plus pelile que cette
derniere, dont la strialion est assez grossiere. La strialion de notre espece est d'une grande delicatesse ; je
n'ai pu I'observer.

Navicula occidcnlalis CI., n. sp.

[PL IX, fig. 4 )
Valve Ian ci^olf^e -a sommets un peu rostres. Longueur, 0,04 a 0,065 mm. Largeur, 0,015 mm.

LE DIATOMISTE 145

Aireaxiale distincte, un peu ^largie au milieu. Stries 13 en 0,01 mm.,radiantes jusqu'aux som-
mets, distinctement ponctuees de pedes, 10 en 0,01 mm., disposees en series ondulees longitu-
dinales.

riab. : Eau douce : Oregon, Pilt River, fossile (Grove Coll.)

Caloiieis bohoinicii CI., ii. s|).

[PL IX, fi(j. 5.)

Valve allongee, a bords tres peu convexes et a sommets subrostres obtus. Longueur
0,055 mm. Largeur, 0,01 mm. Aire axiale assez large, dilatee au milieu en un fascia assez large
atteignant les bords. Lignes longiludinales distincles. Stries presque parall^les, 20 en 0,01 mm,
Hab. : Eau douce : Depots de Breitenbuch (Boheme).

Cyinbella ninpliioxjs (Kjllz.?riiriii.) CI.

[?l. IX, fig. 6.)

Valve presque symetrique, etroite, lineaire lanceolee, a sommets subrostres. Longueur
0,07 mm. Largeur, 0,007 mm. Ligne mediane presque centrale. Aire axiale tr^s Etroite. Aire cen-
trale indistincle. Stries 1 7 en 0,01 mm., au milieu legerement radiantes, puis paralleles, convergenles
dans les sommets. Ponctualion des stries indistincte.

Hab. : Eau douce : Degernas (Suede), fossile.

Cette espece, qui se trouve en assez grande abondance dans le n° 27.3 des Diat. Cleve et Mijller,
a et6 determinee par Griinow comme 6tant le Cymbella navkidacea, var. amphioxys (Xav. ampkioxi/s
Kiitz.??). Notre forme differe Irop du C. naviculacea pour 6tre consideree commo una variete de cette
espece. Quant au Nav. amphioxys de Kiitz. Bac., la figure est trop peu detaillee pour serviraune identifi-
cation.

Cymbella piincllirera CI., n. sp.

(PL IX, fig. 7.)

Valve cymbiforme, a extremites tronquees. Longueur, 0,13 mm. Largeur 0,02 mm. Ligne
niMiane arquee, a fissures terminates retroflexuees. Aire axiale etroite, lineaire, s'^largissant subi-
tement aulour du nodule median en une aire centrale orbiculaire, dont le milieu est occupe
par un stigma. Stries 8 en 0,01 mm., un peu plus rapprochees vers les extremites, radiantes dans
les extremites, distinctement ponctuees par des perles, 15 en 0,01.

Hab. : Eau douce : Oregon, fossile.

Cette espece ressemble beaucoup au C. timiida Breb., dont elle difTere par le stigma central sans fis-
sure, comme chez la C. mexicana.

Tropidoncis (riagiolropjs) pioboscidca CI., ii. sp.

[PL IX, fig. 8, 9.)
Valve lanceolee, rostree. Longueur, 0,075 a 0,085 mm. Largeur, 0,018 mm. Ligne mediane
mediocrement excentrique, a pores centraux pelits et approxirnies. Aile unilaterale, h quelque

I

44(5 LE DIATOMISTE

distance de la ligne mediane. Stries -10 ou 17 en 0,01 mm., Lransversales, a ponctuation extreme-
ment fine.

Hab. : Eaux saumatres : Cameroon (Afrique) (Coll. M.Dusen).

Cette espece se trouve en abondance dans le n° .^38 des types de Tempera et Peragallo. J'ai cru
tout d'abord que c'6tait une forme dii variable T. lepidoptera, niais les differences sont trop f;randes pour
que je puisse maintenir celte opinion. La figure 8 represente un frustule entier, qui repose sur la carene
el I'aile. On voil que la forme que A. Schmidt a figuree dans son Atlas, plancheXL, figure 15, sous le nom
de Amphora mimda, n'est qu'une frustule de quelque espece de Tropidoneis, qu'il est impossible de deter-
miner, mais qui est probablement lie au T. prosboscidea.

Aiiipliiprorn Diisenii CI., n. sp.

iPl. IX, fuj. 10, 11.)

Frustule mince, fortementcontracte au milieu, a segments presque orbiculaires. Longueur,
0,13 mm. Largeur, 0,il mm.; a la constriction, 0,07 mm. Zone connective plissee et finement
striee en travers; stries 17 en 0,01 mm. Valve Ires elevee et comprimee, sans ligne de jonction.
Stries 12 en 0,01 mm. (pres de la ligne mediane), courbees et au milieu (entre les nodules termi-
naux et le nodule central), alternantes, plus longues et plus courtes. Vers la ligne mediane, les
stries sont ponctuees par des perles espacees, 8 en 0,01 mm.

Hab. : Eaux saumatres : Cameroon i^Dusen).

Cette espece remarquable se rencontre rarement dans le n" 338 de Tempere et Peragallo. On la voit,
malgre sa grandeur, avec difficulle, a cause de la transparence de la valve.

Amphora Asliiarii CL, ii. sp.

{PL IX, fig. 12, 13.)

Frustule a sommets largement tronques et a bords convexes. Longueur, 0,005 mm. Lar-
geur, 0,03 mm. Zone non striee, plissee de quatre ou cinq divisions longiludinales. Valve
lunaire, a bord dorsal assez courbe el a bord ventral convexe au milieu. Ligne mediane arquee,
situee a une distance remarquable du bord ventral. Aire axiale large, souvent dilatee autour du
nodule central. Stries de la partie dorsale apparemment non ponctuees, 14 en 0,01 mm., non
interrompues par une ligne longitudinale. Partie ventrale portant une s^rie de stries courtes, 17 en
0,01 mm.

Hab. : Eaux saumatres : Cameroon (Afrique) (Dusen).

Cette espece, qui est remarquable par la largeur de sa partie ventrale, me parait appartenir a la section
de Y Amphora veneta.

Denliciila?Du$enii CI., n. sp.

{PL IX, fig, 14.)
Valve lanceolee, aigue. Longueur, 0,05 mm. Largeur, 0,008 mm. Cotes transversales fortes,
7 en 0,01 mm., alternant avec des tachesmal definies, formanl une seule st5rie entre les cotes.
Hab. : Eaux saumatres : Cameroon (Afrique) (Dusen).

LE DIATOMISTE 147

Celle espece se trouve en aboudanrp dans le n" .'iliSdes types de Tempere et Peragallo. f.a nature

des laches arrondies et raal definies qu'oii voit entre les c6les, m'est inconnue. Elles paraissent appartenir a

une couche interne. Je n'ai pu decouvrirlaponctuation fine qu'on trouve sur les valves des vrais Denticula.

La forme la [iliis rapproclit'ede Df nt. Duscniic|uc jeconnaisse, est le Cytnatopleura marina Lewis (Proc. Acad-

de Philadelpliie, 181)1, p. 6.'t, pL I, fig. i), oii Denhrula f Antillanim CI. et Griin (CI. Diat. from ihe West

Indian Archipelago, p. 14, fig. 26, 1878). Cette forme qu'on trouve le long des c6tes orientaies de I'.Ame-

rique, de New-York jusqu'aiix Antilles, a des c6tes plus ecartees et, entre les cotes, des taches irn-o-u-

lieres. Le Frayilaria anlarctica Schwartz (Sitzungsberichte der Ges. naturforschender Freunde Berlin, 1877),

qui se trouve en abondance dans les n°" 183 et 207 des Diatomees de Cleve et Moller, ressemble par sa forme

au D. Dusenii mais il en differe par les deux .^ories de perles allernantes, qui se trouvcnt entre les cutes.

Odontidium marinum, Griin. (Verb. 1862, p. 338, pi. VllI, (ig. 23), parait aussi !iee a notre espece, mais

la description et les figures ne sont pas assez detaillees pour en permetlre I'identification. Peut-^tre le

Terebrar'ia kerguelensis 0'Meara(Linn. Soc. J. Bot., vol. XV, p, 56, pi. 1, fig. 4), represente-til une forme

analogue a celle mentionnee plus haul.

Bibliographie et Correspondance

.«ynop«lM of the IVavicuIotd niatoms, by P.-T. Cleve. Part. I With 5 plates. Chec

P.-A. Norstedt et Suner, Stockolin. i894. — La premiere partie de cette tres utile et ti'es inleres-
sanle raonographie peut etre obtenue d6s a present, chez MM. Norstedt et Soner, editeurs a
Stockolm, au prix de 16 fr. 70, franco de port.

Tous les diatomistes seront certainement unanimes a feliciter I'auteur d'un travail aussi
considerable et, je dois le dire, aussi bien compris que celui dont nous avons la premiere partie
sous les yeux. Seui, un savant et patient observateurconime Test M. Cleve pouvait lemenera bien.

Voici ce que M. le professeur J. Brun m'ecrit a ce sujet :

« Ce nouveau travail de Cleve que j'ai regu dernierement est vraiment lait avec un esprit
de discernement remarquable. II a parfaitement bien groupe ces navicules. J'ai pu m'en con-
vaincre par un essai que j'avais fait de grouper les formes qu'il a nommees Trachyneis, et cette
partie de son travail coincide juste avec nies observations. J'espere que les nouveaux noms dc
genres qu'il donne seront adoptes. »

Je suis absolument de I'avis de notre savant collaborateur et j'enlretiens le meme espoir, car,
reellement, le genre Navicula et quelques autres genres voisins etaient par trop heterogenes et
demandaieut a etre divises, ainsi que le travail de M. Cleve nous le presente.

Ce travail, ainsi que son litre nous I'apprend, est ecrit en anglais.

La deuxieme partie doit paraitre tres prochainement.

Bioiogiscbe !>»ta(ioa am pi«ener See. iioistein. — M. le D'' Otto Zacharias qui dirige les
observations microscopiques relatives a la faune pelagique et au P/a«^?o« des lacs de Ploen, a
publie dans le deuxifeme bulletin de cette annee du Biologischen Centralblatt, des observations
IrSs interessantes sur les differentes especes de Diatomees qui habitent ces lacs, ainsi que sur leur
abondance relative suivant les saisons. La liste complete des Diatomees p^lagiques de ces lacs ei

148 LE DIATOMISTE

oelles des especes du Plankton sera publiee plus tard. Celte liste doit etre etablie avec I'aide de
M. le comte de Castracane.pour le grand lac de Ploen, et avec I'aide de M. le professeur J. Briin,
pour le petit lac dont la richesse est remarquable.

Le meme bulletin donne la description et les dessins de quatre especes d'eau douce nou-
velles de ces lacs. Ce sonl : Melosira Zacharimsi Cast. ; A (they a Zacharmsi J. Brun ; Stcphano-
disciis Zacharmsi J. Brim, et Rhizosoleiiia longiseta 0. Zachar. — M. Zacharias cherche aussi
a etablir la quanlite de silice que certaines especes (nolamment les Melosira) s'assimilent et
separent de I'eau, pour faire ensuite partie du Plankton. Le poids de cette silice a ete calcule
comparativement a la surface de la masse de I'eau de ces deux lacs. Sur trente-deux kilometres
carr^s de surface, les Melosira fourniraient, aelleb seules, trente-neuf mille quintaux di; silice par
an dans le Plankton. Nous donnerons la-dessus une notice plus complete lorsque lous les travaux
entrepris seront termines.

Les nos 48 etiode I'AiiasUa Be*'. AA. ^icbmidt qui viennent, de paraitre,remplissont une
lacune qui depuis longtemps se faisait seiUir. Les huit planches qu'ils component representent
un grand nombre de Cocconeis qui jusqu'ici etaient resles douteux et sans noms.

La grande habilele, comme dessinateurs, de MM. Ad. Schmidt el J. Brun, et la perfection
de la reproduction, nous permettent d'apprecier, sans le secours d'aucune description, les differences
ainsi que les details de structure qui ont vaiu a chacune des especes representees d'etre distinguee
specifiquement. NaLurellement, ceux que I'accroissement des espfeces nouvelles attriste, auront
encore une bonne raison de desesperer, car il ne s'en Irouve pas raoins de soixante et quehiues,
dans ces huit pJanches seulement. Je serais curieux de savoir ce qu'ils eussent fait s'ils avaient
enti-epris eux-memes ce travail !

Kludiest ill (lie Biology of Tbe DiafoniM. — Tbe Diatoms coasldereil as a ■■roioxoan, by
K.-M cunningbam (TAe Aiiiericaji Monthly Microscopical Journal, m 7, July, and no S, August,
1894). Dans les deux articles precites, I'auteur tente, par une serie de demonstrations et d'expe-
riences, de prouver que les Diatomees appartiennent, non au r^gne vegetal, mais bien au regne
animal, aux Protozoaires ! c'est-a-dire qu'il nous ramene an temps oii I'incertilude etait grande
concernant la place que devaient occuper ces organismes dans la nature. M. Cunningham par-
viendra-t-il a ramener cette vieille question de la nature animale des Diatomees sur le tapis ?j'en
doute!

Ces deux articles sont certainement tres interessants a lire, mais je n'y ai rien trouve qui soil
de nature a demonlrer autrement que cela a deja ete entrepris et d'une fagon irrelutable, que les
Diatomees etaient des animaux ! J. T.

Le Directeur-Gh-ant : J. TEMPERE.

Tours, imp. Paci. BOUSREZ. — Spi^cialitS iJe Public.itions.

I

LE DIATOMISTE VOLU.ME 11

Planche IX

Navicula Henmanii Kciclielt, n. sp. Gross.

Navicula guatemaleiisis CI. et Grove, ii. sp.

— Portion de la valve. —

Navicula delicaliila CI., ii. sp.

Navicula occidenlalis CI., n. sp.

Galoneis bohemica CI., n. sp.

Cymbclla amphiox^-s (Kulz V Griin). CI. —

Cymbella punclifera CI., n. sp.

— H-0 Plagiolropis proboscidea CI., n. sp. <

— 10-11 Amphiprora Dusenii CI., ii. sp. —

— [-11.^ Amphora a'sluaiii CI., ii. sp. —

— |.i Ueuticula Dusenii CI., n. sp. —

Pig.

1

—

2

—

2a

—

3

—

i

—

5

--

6

—

7

1 .000

Paj;c.

14i

."iOO

—

Hi

1.000

—

Mi

1.000

—

Ho

l.OUO

—

145

l.OOQ

—

14.")

1 .000

—

143

500

—

I'lG

8..J0O
0.1000

—

140

10.. 300

11.1000

—

liO

1 .000

—

147

1.000

147

»■.

CLEVE, P. T.. Notes on some Atlantic plankton-orgaDisms,

KONGL. SVENSKA VETENSKAPS-AKADEMIENS HANDLINGAR. Bandet 34. N:o 1

NOTES

ON SOME

ATLANTIC PLANKTON-ORGANISMS

BY

P. T. CLEVE

WITH VIII PLATES

COMMUNICATKD H)(lO, APRIL II

STOCKHOLM

KUNGL. BOKTRYCKERIET. 1'. A. NOUSTEDT Si s6neR

1900

IX

'uriiig the years 1898 and 1899 a, large number of samples of plankton have been
collected from all parts of the Atlantic Ocean by Dutch, English and French ocean liners,
by some wessels of the Dutch and Swedish navy, by whalers in the Arctic Sea and
besides, at some stations, viz. at Vestmanna 6 (S. Iceland), tlie Faroes and the Azores.
Most samples of plankton were collected at the same time as the temperature of the sea
was determined and samples of water for the determination of the salinity preserved.
Professor S. 0. Pettehsson and M. Gust. Ekman have charged themselves with
the purely hydrographical work and left to me the examination of the plankton. In
examining these samples I found a number of forms, which seem to me to be new to
science, and some, the determination of which seems to me to be uncertain for the
want of figures in the litterature. As I intend to publish in a future work my notes
on the seasonal distribution of the Atlantic plankton-oi'ganisms as well as an account of
the mean and extreme temperature and salinity for every species, I wish here to publish
my drawings of some new or doubtful forms.

Although the officers on many of the ocean liners and government wessels have
assisted us in a most liberal way for this extensive hydrographical and biological survey of
the Atlantic, still considerable expenses ha\'e been necessary. For covering these we
have obtained from the fund 'Lars Hiertas Minne» the sum of 7,000 kroner.

I. COPEPODA.
Acartia niacropus. N. Sp.

I'hitu I. Fig. 1 — 7.

Male. Length of cephalothorax 0,88, of abdomen 0,3, of furca, 0,u.), of the longest
seta of the furca 0,4. Breadth of cephalothorax 0,24 millim.

Lateral angles of the last segment of the thorax rounded; margin of the last seg-
ment smooth, without small spines.

Rostral filaments present.

i?. e. 2 of the right fifth foot longer than broad; K. e 3 elongate, with a very small
terminal claw.

4 V. T. CLEVE, NOTES ON SOME ATLANTIC PLANKTON- OKGANISMS.

Feina/f. Length of cf])halothorax 0,ss, of abdomen 0,2r., of furca 0,oo, of the longest
seta of the fiuva 0,4 millini. Breadth of cephalotliorax 0,j.. niillim.

Last segment of tlic thorax with two small finger-like processes. Its margin not
spinous.

The genital-segment of abdomen three times longer than the second segment, which
is as long as the third one. The longest seta of the furca exceeds the abdomen in length.
All seta3 of equal thickness. Furca ncarl}' twice as long as broad.

Rostral filaments present.

Cephalothorax three times longer than broad.

Fifth pair of feet: B. e very short, uniting with B. 2; its interior margin denticulate.

This fine species is most akin to A. nerrucosa Thomps., but is easily distinguished
by the fifth pair of feet botii of the male and the female.

Habitat. The Azores, rare in August and September 1898. Temperature: 21,2 to
21,4. Salinity: 36,25 to 36,2s p. m.

Corj'Cifus long;icaudis Uana.
Plate I. Fig. 8—11.

Male. Abdomen one-jointed, twice as long as the furca. Branches of the furca
at least 7 times as long as broad.

Dimensions: total length 0,k, length of cephalothorax 0,.., of abdomen U,.s, of furca
0,1 millim.

The male of this species has not been described in Giesbrecht's •»Systeviatik und
Faanistik der Pelagischen t'opepodem. It is common in the whole tropical Atlantic.

Kiicliin'lla rostrata Olaus.

I'latc II. Fig. 1 — 12.

Male. Head without ci'ista, l)ut with a subulate rostrum. Fifth foot, six times as
long as its B. '2. Margin of its A', e. 2 not denticulate and of the R. e. 3 smooth, i?. e.
of the posterior anteniuc twice as long as R. i. No triangular scales on the inside of B. I
of the 4^^ foot.

Length of cephalothorax 2, of abdomen 0,5, of furca 0,os millim.

The male has not been described by Giesbrecht's in the Systeiuntik und Faunistik der
Pelagisclien Coj)e2Joden, but he mentions as questionable synonyme Euchceta Hessei Brady
(Chall. Rep. Vol. VIII pag. 63). A comparison af my fig. of the fifth foot with the
di'awing of Brady proves that Euchceta Hessei is exactly the same as Euchirella rostrata.

Some few specimens of the male were found together with several females in De-
cember 1898 oft' the Canaries.

KONGL. SV. VKT. AKAI)EMIP;NS HANDLINGAli. BAND 34. N:tl I. 5

Oiicii'a siibtilis Gncsnu.

I'lalr HI. Fi;,'. 1—11.

Male. Branches of tlio t'urca 'Vt as long as hroad, closely ;i|i|ii-<>NiiiKite; anal-joint
as long as broad. I!, i. of the feet not ending in coiiicMl processes.

Total length: 0,+ (of the female 0,ti); length of ceplialothorax O/jn, of abdomen 0,i,
of furca 0,02; breadtli of cephalotliorax 0,i millini.

This species has been found in the eastern Atlantic from 32° S. to 52° N. The
male was found together with numerous females in a collection from the vicinity ot
Uschant.

II. RADIOLARIA.

Acaiithospha'ra trichophora. N Sp.

riiite \. VvA- 3.

Shell tliin-walled, with irregular, polygonal nicslics, 4 on the radius. Bars thin,
thread-like. Spines few, hair-like, flexuose, twice as long as the r.idius.
Diameter of the shell 0,0^. Meshes 0,oo4 to 0,012 millim.
Atlantic, November 1898, 50° N. 33° W.

Actiiioiiinia(J) Sol N. Sp.

I'hite V. Fig. 2.

Radial proportion of the tliree shells 1 : 2,.-> : 9. Cortical shell thick-ualled, with
circular, regular, six-lobed pores, as broad as the bars. At each nodal-point is a bristle-
like spine, half as long as the radius, thus every pore surrounded l)y a corona of six
bristles.

Diameter of the outer shell 0,00, of the cellules 0,ooi millim.

Found in Janunry 1899 at 45° N. 49° W. in styli- and tricho-pUnikton intermingled.
Temperature 12. Salinity 35,54 p. m.

Owing to the thickness of the cortical shell, tlie interior shells were visible merely
as faint shadows, so I am not quite convinced Avhether the shells are 3 or 2. If the
lattei- be the case, the species belongs to Halioinina and is then nearest akin to H. Iwrrida.

r. T. CLEVE, NOTES ON SOME ATLANTIC I'LANKTON-OKGANISMS.

AiniiliihymeiiiHin elegans. N. S]).
Plate. V. Fig. 1.

Anns ecjual, nun-e tlinn t^vice as long as bi-oad, 5 — fi-jointed; joints increasing in
breadth towards the blunt ends. Their axis a- straight line. Patagiurn enveloping the
arms with the exception of the distal ends.

Length 0,24; breadth 0,09 railliin.

Found at 25° N. .52° W. December 1898. Temperature 24,2. Saliniiy 37, it. Desmo-
plankton.

Aiithocyrtium antheiuis Hke.?
Plate III. Fig. 12.

As there exists no figure of this species, I am somewhat uncertain about the iden-
tification. I have seen a single specimen only, which was found alive at 63° N- 2° E.
(March 1898), where it occurred together with some species of the tricho-type. The
description in H^ckel's Monograph (Chall. Rep. pag. 1273) agrees well with my specimen,
but the dimensions are somewhat dissimilar. On my specimen the cephalis was 0,02 millim.
long and broad and thorax 0,05 long, 0,i broad.

HtECKel's species was found in the abysmal depths of the nothern Pacific. If my
specimen really belongs to Hti-xkel's species, the occurrence above the deep xNorske
Rendex is a fact of considerable interest.

(.'hallongeron brevispiiia. N. Sp.
Plate III. Fig. 14, 15.

Shell ovate, scarcely compressed, with a single, very short conical spine on the aboi-al
pole. Peristome with a single truncate tooth of the same length as the aboral spine.
Structure: quincuncially disposed alveoli, about 4 in 0,oi millim.

Length 0,06; breadth 0,o4 millim.

1 found a single specimen only in a sample from (53° N. 2° E. (March 1898).
Temperature 6,7. Salinity 35, lo.

('latlirocaiiiiinj iiiinutiiin. N. Sp.

Plate IV. Fig. '.I.

Horn of the cephalis fenestrated. Cephalis hemispherical with small subquadrate
pores and a horn of l'/2 the length, surrounded by an irregular network. Length of the
two joints 3:5; breadth 1:2. Thorax with an irregular network: its ribs united by a
circular, irregulary latticed ring. Peristome smooth.

KONGL. SV. Vl'.'l'. AKADKiMIKNS II ANDLINGAR. HAND 34. N:() I. 7

Oiincnsioiis: (•ej)Ii;ilis (l,0J4 long, 0,o4 broad; thorax 0,05 loiio^ and 0,08 inilliin. broad.
Found :it "2 1 S. ;Ui W. (1S9S ()ctol)er). Temperature 22. Salinity ,S7,ji. Desmo-
plnvktoii.

Dietjoceplialiis cj iindricus. N. Sp,

Plate IV. Fis. 10.

Mouth nut constricted, without peristome. Shell thick-walled, with distinct collar
stricture. Length of the two joints 4 : 7, breadth 9:11. Cephalis nearly spherical, large,
witli unequal, circular pores, and rough of numerous, short spines. Tliorax cylindrical,
with rounded, unequal pores.

Length nf the shell 0,i millim.

Found at l.r N. 71° W. (F'ebruary 1898). Temperature 27. Besmo-plankUm.

This species differs from D. liispidiin Enn. in the cylindrical, not funnel-shaped,
tliorax and from D. ohtusus by the spiny cephalis and the unequal pores.

Dictyoceras iieglectum. N. Sp.

Plate IV. Fig. 5.

Shell with two distinct strictures. Length of the three jtMuts 1 : 3,5 : 1,5, breadth
1:3:4. Cephalis almost spherical, with a strong horn, nearly twice as long, and small
irregular circular pores. Thorax campanulate, with three small triangular lattice wings.
Cellules subregular, hexagonal, quincuncially disposed, 2,5 in 0,oi millim., similar on the
thorax and abdomen.

Length of the three joints: 0,o2 : 0,05 : 0,03; breadth 0,02 : 0,oii : 0,08 millim.

Tropica] Atlantic 11°— 33"' N. 32°— 76° W. Mean temperature 25, i. Mean salinity
36,04. Desmo-plankton.

Eupliysetta pusilla. N. Sp.
Plate III. Fig. IG.

Shell egg-shaped, without apical horn; structure double: longitudinal lines 11 in
0,01 millim., and very small alveoli, quincuncially arranged, 19 in 0,oi millim. Small feet
subulate; odd foot half as long as the shell, not branched.

Length 0,06; breadth 0,04 millim.

Very rare at 45° N. 49° W. (January 1899). Temperature 12. Salinity 3.'), 54.

Halioiniiia echiiiosphfera. N. Sp.

Plate V. Fig. 5.

Cortical shell thick-walled, 2l'2 times broader than the medullary shell, with regular,
circular, hexagonally framed pores as broad as 1he bars. The outer openings of the pores
are sixlobed, lobes ending in short, conical spines.

8 p. T. CLEVE, NOTES ON SOME ATLANTIC PLANKToN-OROANlSMS.

Diameter of the outer shell 0,i, of the interior U,04, of the meshes 0,oi millira.
\'ory rare at 45° N. 49° W. (1899 January). Temperature 12. Salinity 35,54.
Similar to H. mditoinma, but smaller, with thicker bars and smaller meshes. The
thickness of the cortical shell prevented all examination of the medullary shell.

Halioinma irregulare. N. Sp.

Plate V. Fig. 4.

Pores of the cortical shell irregular, rounded, of different size and forrn. Spines
stouter main-spines and smaller by-spines, the former Vo of the radius. By-spines scat-
tered at intervals. Cortical shell thin-walled, 3 times as broad as the medullary shell.
Poi-es irregular rounded, 3 to 9 times as broad as the bars. Medullary shell with rounded,
smaller pores.

Diameter of the outer shell 0,22, of the medullary shell 0,07, of the meshes 0,oi to
0,03 millim.

Very rare at 45° N. 49° W. (January 1899). Temperature 12. Salinity 35,r,4.

Halioinma spinulosuin var. *)

I'late V. Fig. 7.

I have met with specimens having tuio concentric, exterior shells with very wide
irregular meshes and thread-like bars. The interior shell had, as usually, very regular
hexagonal meshes. There is thus no other difference between this form and the normal,
than that the variety has three, in stead of two, shells and should therefore be classified
as Echinomma. It seems as were the number of exterior shells variable, and it may be
possible that Arachnosjjha'ra comprises forms with an increased number of shells, espe-
cially as the interior shell of Haliornma spinulosiim is similar to those of Arachnosphara
iiiyriacantha and A. oligacantha.

Heliosphfpra minuta Cr..
riato VI. Fig. 2.

Thick-walled, 5 to 6 times as broad as the meshes. Pores regular, all equal, hexa-
gonally framed- Main-spines three sided pyramidal, few, l',2 times as long as the radius.
By-spines short, acute, arising from the nodal points of the meshes.

Diameter 0,05 to 0,0?; pores 0,ooii; bars 0,oo6, main-spines 0,o2 to 0,ob millim.

Rare at 41° N. 21°— 23^W., 49^ N. 18° W., 62° N. 11°W. (March 1898) and 17° N.
71° W. (August 1898). Temperature 11,7, mean of 4 observations, max. 14,y, min. 8,
exceptionally 27,2. Salinity 35,63, mean of 3 obs., max. 35, s7, min. 35,37.

*) The same form has licen tignrcd hy Jorgensen (Borgens Museums Aarbog 1899, N. (!, PI. Ill, fig. 18)
as Araclmospha'ra dichotoma.

KONGL. SV. VET. AKADEMIENS IIANDLINGAH. BAND 34. N:0 i.

Hexacoutium nrmatnni. N. Sp.
Plate VI. Fig. 6.

Cortical shell thick-walled, witli regular, honeycomb-like network. Meshes funnel-
shaped, with circular iiinci- ;ind hexagonal outer apei^ture, as l)road as the bars, about 7
on the radius. Main spines strong, three-sided prismatic, as long as the radius of the
outer shell. By-spines at every nodal point, short, bristle-like. Radial proportion of the
three shells 1:3:8.

Diameter 0,n; length of the main spines 0,or,; basal breadth of the main spines 0,02;
diameter of the meshes 0,oi millim.

Rare at 56° N. 17°. W. (November 1898). Tnuperature 11,6. Snlinity 35,27. Styli-
Ijlankton.

Nearest akin to H. favosuin, from which it differs b)- tlie smaller meshes and
the stronger main spines.

Hexacontium hostile. N. Sp.

Plate VI. Fig. 4.

Radial proportion of the three shells 1:3:9. Outer shell thick-walled, with ir-
regular, rounded pores, 1 to 5 times as broad as the bars. Main spines strong, three-
sided prismatic, slightly spirally twisted, t^\■ice as long as the radius. By-spines bristle-
like as long as the diameter of the pores.

Diameter of the outer shell 0,09, of the middle 0,o3, of the inner 0,oo9; diameter
of the pores 0,oo6 to 0,oi6; length of the main spines 0,os, their basal bi-eadth 0,024 millim.

Rare at 56° N. 23° W. (November 1898). Temperature 10,8. Salinity 35,32.

Hexacontium setosuiu Hkl.?

Plate V. Fig. 6.

This species (Chall. Rep. Radiol, pag. 198) has not been figured, of which reason
the identification is doubtful. The radial proportion of the three shells 1:4:7. Diameter
of the outer shell 0,i4, of the middle 0,04, of the inner 0,02; diameter of the cortical pores
0,01 to 0,03; breadth of the bars 0,oo4; length of the main spines 0,06 millim.

Rare at 45° N. 49° W. (January 1899). Temperature 12. Salinity 35,54.

My specimen occurred in styli- and trichoplankton intermingled.

Hexastjius nobilis. N. Sp.
Plate VI. Fig 1.

Shell thick-walled. Pores regular circular, hexagonally framed, 10 on the radius.
Six main spines triangular pyramidal, with straight edges, as long as the radius; their

K. Sv. Vet. Akad. Handl. Band 34. N:r 1. 2

10 p. T. CLEVE, NOTES ON SOjME ATLANTIC PLANKTON-OROANISMS.

bases as broad as two meshes. By-spines bristle-shaped, arising from all nodal points of
the meshes, half as long as the main spines.

Diameter of the shell 0,i6; length of the main spines U,o6 millim. Meshes 9 in 0,oi
millim.

Very rare at 19° N. 60° W. (1898 November). Temperature 27,5. Salinity 35,22.

Lainproraitra erosa. N. Sp.

Plnte IV. Fin; 2— .3.

Shell flat conical, with slight collar stricture. Length of the two joints 1:4;
their breadth 1 : 3. Cephalis hemispherical, with a horn of IV2 the length and with ir-
regular rounded pores of unequal size. Thorax with large rounded pores of unequal size.
Its margin with distant, frequently double teeth.

Cephalis 0,02 long, 0,03 broaxl; thorax 0,oii long, 0,i6 millim. broad.

Very rare at 45° N. 49° W. (January 1899). Temperature 12. Salinity 35,r,4.

Psilomelissa lougispiua. N. Sp.

Plate IV. Fig. 4.

Shell smooth, with strong collar structure. Length of the two joints 4 : 3, breadth
1:1. Cephalis large ovate, with numerous scattered circular pores of unequal size, larger
and more crowded towards the collar stricture. Thorax short cylindrical, with scattered
circular poi-es. From the collar stricture there arise three divergent spines of equal
tliickness throughout their whole length, as long as the cephalis.

Cephalis 0,04 long, (),03 broad; thorax 0,028 long, 0,o:i millim. broad.

Western tropical Atlantic (1898 January at 32° N. 74° W.; May at 41° N. alMV.;
December at 18' N. 67" W. Temperature 19 to 26, s. Salinity 34, 8s to 36, 01.

Quadrilonche crux. N. Sp.

Plate IV. Fig. 1.

Four equatorial spines with apophyses, the other neadle-sha])ed. Equatorial spines
with conical ends, gradually narrowed towards the centre, winged along their wliole length,
except at the conical end.

Length of the cross 0,i6 millim.

Western tropical Atlantic, sparingly from 26^ S. to 36° N. Temperature 25,4, mean
of 13 obs., max. 28, min. 21,7. Salinity 36,4o, mean of 8 obs., max. 37,43, min. 34,88.

KONGL. SV. VET. AKADEMIENS HANDLINGAK. BAND. 34. N:U I. 11

Sethoconus criiiitus. N. Sp.

riato III. Fis. 13.

Cephalis subsphfi'lciil l;iri;e, with miiuerous In'istlc-.sli.'iprd horns jiiid tdosu polygonal
ineslic'S of different size. Collar constriction deep. Tliui-ax conical, with straight outline,
gradually increasing in breadth towards the wide open month. I'orcs of the thorax siniihir
to those of the cephalis, polygonal and of different size, much broader than tlie thread-
like bars.

Cephalis 0,03 long and broad. Thorax O,ori long and broad. Collar constriction
0,02 millim.

Sparingly along the N. coast of S. America and in the Florida current, 7° — -ll'N.
53^ — 75' W. Temperature 22,4 to 28. Salinity 83,88 to 36,56.

Sethocyrtis pyrum. N. Sp.

Plate IV. Fit;. 6.

Shell thick-walled, pear-shaped, with slight collar stricture. Length of the two

joints 1 : ti, breadth 1 : 4. Cephalis hemispherical, with a, small horn of half the length

and unequal small pores. Thorax inflated, with circular, regular pores, quincuncially

arranged and as broad as the bars. On the nodal points short spines arise. Mouth flat,
half as broad as the thorax.

Cephalis 0,oi2 long, 0,o2 broad. Thorax 0,072 long and U,08 millim. broad.

Very rare at 45° N. 49° W. (January 1899). Temperature 12. Salinity 35,54.

Spermatogonia antiqua Leud. Fortm.
Plate III. Fie. 17, 18.

Dr. Leudugeu Fortmorel described in 1(S92 (Diatomees de la Malaisie. Annales du
Jardin botan. de Buitenzorg. Vol. XI pag. 49. PI. IV, fig. 8) under the above name an
organism from the Malay Archipelago, which he considered as a diatom. The figure has
been reproduced in Vax Heurck's Treatise on the diatomacee (1896) pag. 541 with the
remark ns it a diatom?». This form is by no means rare in the tropical xAtlantic and
cannot be a diatom. It is a part of an organism, of which I have however seen oidy
alcohol-preserved specimens. The neadles, called Spermatogonia, are by their arrow- head
like ends fastened in groups on a lij'aline sack, which encloses, besides a number of
smaller granules, a larger cucumber-like body. This body, which treated with soda shows
a peculiar structure of longitudinal and transverse lines, reminds of the central capsule
of the radiolarians. If so, the hyaline sack should correspond to the calyrana. But, on
the other hand, there is no radiolaria known, wich otters any distant relation to
Spermatogonia. From tlie jJieeodarian it difters by the entii-ely dift'erent central capsule.
In all cases this form is no diatom, and, if a radiolaria, it belongs to a quite new type.

12 p. T. CLEVE, NOTES ON SOME ATI.ANTIC PLANKTON-ORGANISMS.

The range of distribution in the Atlantic is from Rio Janeiro to 56° N., chiefly in
the west. T'emijeratare 24,5, mean of 26 obs., max. 28,4, niin. 9,6. Salinity 35,39, mean
of 23 obs., max. 36,40, rniii. 33,93.

Theocoims junonis IIkl. att".
Plate IV Fig. 8.

I have reproduced in Fig. 8 a drawing of the only specimen I have seen, as it is
of considerable interest for its occurrence W. of Norway. It is doubtless akin to T. jovis
or to T. jimonis, but does not sufficiently agree with any. It was found in March 1898
at 62° N. 2° E. (temperature 7,4. Salinity 35, 12). The water was very poor in plankton,
as the tow-net catched in half an hour some few plankton-specimens only, such as Cosci-
nodiscus oculus iridis and several radiolarians, not found at other spots in the Atlantic.
T. junonis was taken by the Challenger Expedition from great depths east of Japan. Theo-
conus jovis has been found in the abysmal depths of the central Pacific.

Length of the three joints 1 : 3,5 : 2, breadth 1:4: 5. Cephalis 0,oi6 long, 0,02
broad. Thorax U,05 long, U,o« broad. Abdomen (incomplete) 0,03 long, 0,i millim. broad.

Theocyrtis aculeata. N. Sp.
Plate IV. Fig 11.

Shell thick-walled. Length of the three joints 1:2:4; breadtli 1:3:3. Cephalis
hemispherical, with a strong hoi-n, longer than the cephalis. Thorax slightly inflated.
Abdomen cylindrical, with several rows of strong aculei towards the mouth. Pores of
the thorax and abdomen of nearly equal form and size, circular, regular, quincuncially
disposed, 3 to 4 times as broad as the bars.

Length of the three joints: a 0,025, h 0,06, c 0,ii; breadth: a 0,03, b 0,076, c 0,o9.
Horn 0,04 millim. long.

Found in November 1898 between 56° N. 17° W. and 48° N. 29° W. Temperature
10,8 to 15. Salinity 35,2? to 35,44.

Theocyrtis turris. N. Sp.

Plate IV. Fig. 7.

Length of the three joints 1:3: 4, breadth 1:3:3. Pores of the thorax and ab-
domen of the same form and size. Cephalis small, hemispherical, with some scattered
pores and a liorn of the same length. Thorax conical; abdomen cylindrical. Pores
rounded, or rather subhexagonal, broader than the bars, quincuncially arranged. Length
and breadth of the cephalis 0,oi, of thorax 0,03. Abdomen 0,045 long, 0,05 millim. broad.

Very rare at 45° N. 49° W. (January 1899). Temperature 12. Salinity 35,54.

KONGL. SV. VKT. AKAUEMIENS HANULINGAH. ISANI) 34. N:() I. 13

Trj p;inosph.Tra brachysiplioii. N. Sp.

Plate VI. Fig. 3.

Shell a regular sphere. Pores of unequal size; the larger prolonged in a very sliort
tube, with two or three teeth.

Diameter: 0,i5, of the larger [)ores 0,oi7 milliui.

Found very rarely at 56° N. 17° W. (November 189S) and at IT^N. G6° W. (De-
cember 1898). Teiiipernt'uro 11/; to 12. Salinity 34, eo to 35,J5.

III. DINOFLAGELLAT^.

Ceratiuiu (tripos var.) arcuatum Gouuret.
Plate VII. Fig. 11.

GouRRET has described (Ann. du Musee d'Hist. Naturelle de Marseille; zool.. Vol. I
1883 n:o 8, pag. 25, PI. II, Hg. 42) a form of C. tripos, which I consider, although with
a some hesitation, to be identical with the Atlantic form.

It is rather common in the tropical Atlantic from 29° S. to 48° N.

Ceratium (tripos var.) arietimiiii. X. Sp. *)
Plate VII. Fig. 3.

This form, Avhich belongs to the tripos-type, is very constant and could be consi-
dered as a distinct species. I have seen it in samples from the Indian Ocean and the
Atlantic, chiefly on the area between the Azores, the Engl. Channel and New York. It
occurs besides, but sparingly, in the N. Equatorial current, the Antilles current and in
the Caribbean Sea. It belongs to the si yli- plankton.

Ceratium (tripos var.) azoricuni. N. Sp.

Plate VII. Fig. 6, 7.

This form is nearly related to the typical C. tripos, but differs by smaller size and
short apical horn. It occurs round the Azores and W. of the Spanish Peninsula. I have
also met with this form in plankton from "25° S. 7° E.

Ceratium (furca var.?) belone. N. Sp.
Plate VII. Fig. 13.

This form, which is evidently nearlj- akin to C. furca, is very rare in the Atlantic
and has been found in samples from 10° N. 53° W. and 33°— 34° N. 15° — 12° W., thus
in the western and eastern tropical Atlantic.

*) J0RGENSEN (Bcrgeus Museums Aarbog 1899, X. \'I, I'l. II. tig. 1 1) names tliis form Ccfafiiiiii tiipos
arcuatum forma heterocampta. j0RGENSElsS work was not iiul)lislied when this jiaper was written.

14 p. T. CLKVE, NOTES ON SOME ATLANTIC PLANKTON-ORGANISMS.

Ceratiuin coutortum Gourret.

Plate VII. Fig 10.

This species, akin to C. tripos, is too constant for being considered as a mere variety.
It lias been described by Gourret in Annales du Mus. d'Hist. Nat. de Marseille; zool. vol. I
n:o 8, 1883, PI. 11, fig. 33. Schutt has figured it in Pflanzenleben d. Hochsee, pag. 268,
Vll b., but not named it. It occurs in the Mediterranean, Indian and Pacific. In the
x^tlantic it is rather cotnmon in the troi)ical parts, E. of S. America and VV. of Africa.
If a line be traced on the northern hemisphere from the Cape Verde to the Newfoundland
Banks the space on the left of this line repi'esents the area of distribution of this species.

Ceratium curTicorue v. Daday.
Plate VII. Fig. 2.

This constant and characteristic form described by v. Daday (Termezetrajri fiizetek
a mns. Hung. Budapestense vulgata 1887 — 88, PI. Ill, fig. 4, 8, 12, 14) as a variety of
Cer. tripos, has been figured (without name) in Schutt Pflanzenleben der Hochsee, pag.
268, VII a.

I have met with this species in samples from the Red Sea, the Indian ocean and
the tropical Atlantic, where it occurs rather common in ths Equatorial currents, the
Brazil current, the Florida current towards the Newfoundland Banks as well as east
thereof between 40° — 45° N., in the Sargasso Sea, at the Azores and the Canaries.

Ceratium flagellifermn Cl.

Plate VII. Fig 12.

I have proposed this name in 1899 (Kongl. Sv. Vetensk.-Akad. Handl., Vol. XXXII,
n:o 3, pag. 1, nomen nudum) for a characteristic form of the tropical Atlantic. It has
been figured by Schutt (Pflanzenleben der Hochsee, pag. 267, fig. 77, V. b, without
name) as a form of Ceratium trijios. It may possibly be the same as C- tripos var. in-
flexum Gourret, but I dare not identify them. This species is remarkable for the small
size of the body and the very long horns, the posterior of wich have a characteristic
flexure. This species is very common in desnio-ijlankton of the whole tropical Atlantic,
from 29° S. to 45° N.

Ceratium(.') Iiyiierboreum. N. Sp.

Plate VIII. Fig. 14.

By the above name I denote a very small, but characteristic dinoflagellate, of
which I have not been able to distinguish the tabulation nnd which pos.sibly may belong
to Peridinium. The longitudinal axis measures 0,07 and the transverse 0,o:> millini. The
membrane has a coarse and irregular areolation.

KONOr,. SV. VET. AKADEMIENS HANDLINnAH. BAND 34. N:0 I. 15

I t'oiuid this species in samples from Spitzbergen, collected in August 1898 (80°
31;N. 1<S.")0'K.) and the same month 1899 (80° N. l(i°E.). Temperature — 0,30 to
+ 2,4-.>. ISnlinity ih,-M\ to 3;^, 9:). It is thus to be considered as an arctic neritic form.

Ceratium paradoxides. N. Sp.
Plate VII. Fig. 14.

I propose this name for a form, nearly akin to C. iunuJus. It is characterized by
the cellular reticulation of the membrane. I have seen it, but very rarely, in samples
from tiu' Xe\vfoun<lIaii(l Hanks, the Azores and the Canaries.

Ceratium rauipes. N. Sp.
Phite VII. Fig. 1.

This rare and remarkable form has been figured by Souutt in Pflanzenleben der
Hochsee, pag. 267, fig. 79, \'I1I b. but without name. Lemmekmann (Abh. Nat. Verein.
Breraens. Yo\. XVI, Part 2, pag. 346) names it C. tripos var. digitatum, but as Schiitt
has already used tlie name <li(/itatuin for another different species, a- new name becomes
necessary.

This form occurs in the tropical Atlantic, in the Equatorial, Antilles and Florida
currents, also round the Azores, or between 12° and 49° N.

Ceratium reflexum. N. Sp.
Phite VII. Fig. 8, 9.

Tills form, characterized by the divergency of the posterior horns, of which one is
nearly parallel to the apical horn, is very rare and has been seen twice onl}-, viz. at 19° S.
31° W. and 38° N. 47° W.

Ceratium (tripos var.?) volans. N. Sp.

Pliite VII. Fig. 4.

This form is characterized by the straight and very long posterior horns, which
proceed in a right angle to the apical horn. They become first towards the distal end
somewhat bent towards tlie apical horn.

This species is common in the tropical Atlantic, and it may be possible that it is
the same as Ceratium earriense Gourret, which I dare not decide without comparing
original specimens.

Ceratium (tripos var.?) vultur. N. Sp.

Plate VII. Fig. 5.

This species, which is characterized by the angular flexure of the posterior horns,
occurs frequently in chains. 1 have found it in samples from the Indian ocean and from
the tropical Atlantic between 21° S. and 45° N.

16 p. T. CLEVE, NOTES ON SOME ATLANTIC PLANKTON-ORGANISMS.

Diiiophysis Vanlioffenii Ostenf. *)
Plate VIII. Fig. 3.

Under the name D. (/rnnulata I have described a small form (Kongl. Sv. Vet.-Akad.
Handl., Vol. XXXII, n:o 3, pag. 39, PI. IV, fig. 7) from Spitzbergen, where it was found
among drift-ice. This form seems to me to be a small variety of a widely distributed
arctic species, named by Vanhoffen »Z). ovata Clap & Lachm.» (Gronl. Exp. 1891 — 93.
Vol. II, 1 part, 1897, PI. V, fig. 7). Ostenfeld (lagttagelser over overfladvandets tem-
peratur, saltholdighet og plankton, 1898, pag. 58) proposed the name D. Vankojfenii,
which I accept as it denotes the typical form, and my name a dwarf-form only. Tliis
species, which seems to have been confounded with D. Michnelis (Ehb.) Auriv. or D.
rotundata, is well characterized by its thick, coarsely areolated membrane, the upper part
of which scarcely proceeds beyond the girdle. The apical part has frequently some short
.spines.

I have seen this species in a collection from Jeddo Bay (Japan) and very frequently
in specimens from the northern Atlantic, between 81° and 52° N. Temperature 5,9, mean
of 21 obs., max. 9,8, min. — 0,9. Salinity 34,35, mean of 21 obs., max. 35,4i, min. 32,03.

Peridiuium diabolus. N. Sp.
Plate VII. Fig. 19, 20.

This species has been figured by Murray and Whitting (Trans. Lin. Soc. of
London, 2 Ser. Bot., Vol. V, Part 9, PI. XXIX, fig. 4 b) as a variety of F. divergens.
It is such a characteristic form that it merits to be considered as a species, remarkable
for its small size and the very strong posterior horns. I have found it in samples from
the Indian ocean and the Atlantic, where it has been observed from the region of Cape
Verde to the coasts of Portugal and near the Azores, besides S. of the Newfoundland
Banks and E. of Cape Hatteras. Temperature 14,8 to 24. Salinity 36 to 36, 4o. Belongs
to the styli-2)lankton.

Peridiuium elegaus. N. Sp.
Plate VII. Fig. 15, IG.

This species is nearly related to P. divergens and lias been figured by Murray &
Whitting (Trans. Linn. Soc. of London, Ser. 2, Vol. V, part 9, PI. XXIX, fig. 4 a) as a
variety of the named species. It differs from P. divergens by larger size (length 0,2,
breadth 0,i millim.), by the absence of teeth at the basis of the posterior horns and by
the ends of the girdle not being oblique. The longitudinal axis is slightly oblique to
the plane of the girdle.

*) Diiiophysis iiorvegina (Clap, et Lachm.) J0RGENSEN (Rcrgens Museums Aarbog 1899, X. VI., PI. I,
fig. 3 — G) and D. acuminata J0RG. /. c. fig. 7 — 9.

KONfiL. SV. VKT. A!C,\nF,MIF.NS H A\'l)MNn AH. BAND 34. N:0 I. 17

This species has been found in samples from the Indian ocean as well as from the
Atlantic, where it occurs in the tropical part, at least from 21° S. to 47'' N. Temperature
23,8, mean of 4.") ohs., max. 28,:!, min. 10. Salinity 35,84, mean of 40 obs., max. .'i7,J8,
min. 32,87. It belongs to desino-plajikton.

Peridiniiim exiguum. N. Sp.
Plate VIII. Fig 5.

This species is also nearly akin to P. divergens, but differs in the small size
(length 0,or. — 0,or,, breadtli 0,04 millim.), the coarse areolation, the serrated posterior horns
without basal teeth and in the oblique girdle.

I haA'e found it in samples from the Azoi'es (August 1898) and from the coast of
Portugal (rTune 1898). Tempei'ature 21,2. Salinity 36,25. It belongs probably to ntyli-
plankton.

Peridinhim oceaiiicuiii Vanhoffen.
Plate VII. Fig. 17, 18.

In the »Peridineen der Planktonexpedition» (PI. XIII, fig. 44) Schutt has figured,
as a variety of P. divergens, a common atlantic form, which Vanhoffen (Gronl. Exp.,
Vol. II, 2 part, PI. V, fig. 2) names P. oceanictnn. The same form was, also in 1898,
named by Aurivillius (Kongl. Sv. Vet.-Akad. Handl., Vol. XXX, n:o 3, pag. 96) Perid.
div. var. ohliqua.

It is a very constant, easily recognised form, which I have seen in samples from
the Red Sea and the Indian ocean. It occurs in the Atlantic chiefly in the region of the
Azores and N. thereof, in the spring across the whole Atlantic, between 40"^ and 50° N.,
whence it spreads, during the summer, towards Greenland, into the Irminger Sea and
across the Faroe Channel into tlie North Sea and the Skagerak. Temperature 12,9, mean
of 82 obs., max. 22, min. 3. Salinity 35,45, mean of 28 obs., max. 36,25, rain. 34, le.
(For the calculation of the means only such samples have been used as contained this
form in any abundance) It is a typical styli-planhton form.

Peridiniiim pallidum Ostenf.
Plate VII. Fig. 21, 22.

Under the above name Ostenfeld (lagttagelser over overfladvandets temperatur,
saltholdighed og plankton in 1898, pag. 60, 1899) has distinguished a form nearly related
to P. pelhicidum, but with oblirpie posterior horns.

It is an arctic form, that ranges between 39° and 79° N. Temperature 8,5, mean
of 45 obs., max. 19,4, min. 0. Salinity 34,87, mean of 45 obs., max. 35, a7, min. 32,43.
It belongs to trieho-plnnkfon and to the nortlirrn ncritic plnnkton.

K. Sv. Vet. Aknil. lIuM.ll. liaml .14. N:n 1. 3

18 p. T. ("LEVK, NOTES ON SOME ATLANTIC PLANKTON-ORGANISMS.

Plialocroma niiniitiiin. N. Sp.
Plate VIII. Fi,g 10, 11.

Longitudinal axis 0,05, sagittal axis 0,o4, transverse axis 0,o2r. inillim. Areolation
coarse, 3 to 4 ai'eoles in 0,oi raillim.

I have found this small form twice only, viz. at 4r N, .57° W. (July 1899) and at
4rN., (32" W. (August 1899). Temperature 22 to 24,4. Salinity 33,88 to 36, i3.

Steiiiiella(?) punctata. N. Sp.
Plate VIII. Fig. 4.

This species is characterized by its biconical form, solid membrane and coarse
areolation. Longitudinal axis 0,ii, sagittal and transverse axis 0,o6 millim. A nearly
related form has been described by Murray & Whitting (Trans. Linnean Soc. of London,
ser. 2, Bot., Vol. V, Pi. XXVI, fig. 4) as Ceratiuia biconicuin, which also pi'obably belongs
to the genus Steiniella.

I have found this form once only in a .sample from 48° N., 24° W. (August 1899).
Temperature 19,4. Salinity 35,r,3. Styli-planhon.

IV. CYSTJE.

Cysta linibata Cl. *)
Plate VIII. Fig. 15.

By this name I propose to denote an organism, that has already been observed by
Hensen (»We]liger Statoblast» S**' Ber. d. Kieler kommission, PI. IV, tig. 28, 29), but has
not got a name. It represents probably a stage in the development of some other orga-
nisms, perhaps some dinoflagellate, still, as it is of a certain importance to have a name
for it, I propose the above one. It is a cellule of nearly spherical shape, in diameter
about 0,05 millim., filled by a granular, probably greei^, mass. The membrane is somewhat
thick and surrounded by a hyaline, plicate girdle, twice as broad as the enclosed cellule.
Tliis form is not very rare in the northern Atlantic, the North Sea and the Skagerak.

Hyalosphysa delicatula. N. Sp.
Plate VIII. Fig. 22.

By this name I denote an unknown unicellular alga, which was found in samples
IVoin the Azores (August 1898). It is remarkable for the very thin membrane and small
scarce chroraatophores scattered on the inside of the wall. The form of the cellules is

*) Since the aliove was written ,T0RG[ENSEN (Bergens Museums Aarbog 1S99, ]). 48) lias named tliis
organism Pfrronphrrrd Afohii, wliirli name has priority.

KONGL. SV. VKT. AKADEMIENS HANDLING Ali. BAND 34. N:0 I. 19

slightly cvliiidi'ical or iilmost iilobulai'. Di.-uaetcr U,oii to 0,os luilliui. As I luive seen
ak'ohol-j)reser\ed specimens only, I am uniil)Ie to decide whether the chromatophores are
green or yellow.

I'yrocystis hamulus. N. Sp.
rUitc VII. Fig. 23.

Tlii.^i eliaracteristic cysta, perhaps a stage in the development of some dinofliigellate,
seems to he akin to Pyroc. lunula. It is remarkable for the small body, that suddenly
goes o\cr in two long, towards the distal part bent horns. I have found it in samples
from the Indian ocean and in the Atlantic between IT — 32° N., 47° — 74° W., in desmo-
Ijlanktou.

Xauthidium paucispinosuiu. N. Sp.
I'hite VII. Fig. 24.

This cysta is prol)aI)ly the same as has been figured by Hensen (S*" Ber. d. Kieler
kommissioii, Pi. IV, fig. ol) as »dornige cyste». I have met with it both oft' the N.
coast of South America and at the Azores.

V. DIATOMACE^.

Asterionolla notata Gkun.
Plate VII. Fig. 32.

Grunow has figured a valve and t-wo frustules of this species (Van Heuuck Synopsis,
PI. LII, fig. 3), whieli I hiwe found in samples from the Azores. The frustules are con-
nected by their basal part to comb-like colonies, which are twisted in dift'erent ways.
Besides, the frustules in one colony are frequently directed in various directions.

Asteroniphalus atlanticus Cl. and As. lieptactis Rlfs.

Plate VIII. Fig. 6—9.

In the year 1873 I published a figure of an Asteroniphalus (Bih. till Kongl. Sv.
Vet.-Akad. Handl., I, n:o 13, PI. IV, fig. 19), found in bottom-mud from Davis Strait,
wiiich I supposed to be A. Brookei Bail. Later, in 1896 (Bih. till Kongl. Sv. Vet.-Akad.
Handl., Vol. XXII 3, n:o 4, pag. 5) I proposed to name this form, which occurs in the
northern Atlantic, A. atlanticus. Gkan (Den Norske Nordhavs Expedition 1876 — 78.
Protophyta 1897, PI. IV, fig. 63) has given a good figure of the same form. In a recent
publication (lagttagelser over overfladvandets temperatur, saltholdighed og plankton fra
Islandske og Gronlandske skibsrouter in 1898, pag. 52) Ostenfeld means, that A. atlanticus
is a small form only of A. hcjAactis. This opinion seems to me to be erroneous.

20 1', T. CLEVE, NUTEt^ ON SOME ATLANTIC I'LANKTON-OKGANISMS.

as will be scon from the figures, PI. VIII, fig. 6 — 9. Of these the fig. 6 represents ;i
.speeimen of A. Iwptactis (23'i of May 1898 58° 48' N., 18°45' W., Ostenfeld's collection),
the fig. 9 a very small specimen of A. atlanticxis from the same gathering. Tlie fig. 8
represents a specimen of ordinary size from Davis Strait and the fig. 7 a specimen from
the coast of Portugal, the largest I have seen.

The specific difference may be seen from the follo\\ing comparison:

A. heptactis. A. atlanticus.

Size 0,05 to 0,1 millim. 0,o25 to 0,06 millim.

Radial proportion of the umbilical

space and the limbus 1:3. 1:2.

Alveoli in 0,oi millim 6. 12.

Geographical distribution .... 26° S.— 63° N. 46° N.— 78° N.

Plankton-type Styli-plankton. Cheto- and triclw-pJankton.

That A. heptactis and A. atlanticus are different species cannot be doubted, but
the question whether A. atlanticus and A. Broohei are identical or not, is more difficult to
decide ^\'ithout comparison of original specimens. Gkeville's figure of A. Brookei from
Kamtchatka (Trans. Mic. Soc, \o\. VIII, PI. IV, fig. 18) has 10 alveolate fields, else it
seems to agree well, but as the minute structure has not been accuratelv described, the
identification is impossible. It Avould be of a great interest to settle that question.*)

Chictoceros difficilis. N. Sp.
riiitc VIII. Fig. 16—18.

Chains loose, of quadrate cellules, separate by large rectangular or subhexagonal
foramina, half as long as the cellules. Cellules thin-walled, in sagittal-longit. i)Osition
(juadrate -with fiat valves. Cell-contents (as far as could be ascertained on alcohol-preserved
specimens) with only one chromatophore. All a-\vns very delicate. Endocysts \n the
middle of the cellules, biconvex, smooth, but with a periplierical row of small puncta.

Longitudinal axis 0,oo.-. to 0,oo8. Sagittal axis 0,oo8 to 0,oi. Endocysts 0,oo7 to 0,oi
millim. Sterile specimens resemble C. balticus Cl. (Bih. till Kongl. Sv. Vet.-Akad. Handl.,
V'ol. XXI 3, n:o 5, pag. 25), but the endocysts are different.

This species was found in September 1899 at 59" N., 1° 2' W. (temperature 11,8,
salinity 35,3?) together with forms that belong to tripos- and sira-plankton.

Cbaetoceros longisetiis. N. Sp.

Plate VII. Fig. 2.5—20.

Chains composed of numcrnus cellules, stniiglii, Ihiii-walled, without foramina.
Cellules in longitudinal-sagittal position (juadrate, with flat valves. Awns arising from

*) When this paper was in the jji'ess, I received samples from the southern Atlantic, which cnutained
aliuiulantly A. Hookeri Ehb. This antarctic form agrees perfectly with the boreal A. athmtirus, which name
consciiucntly must be exchanged for A. Hookeri.

IvONtiL. SV. VET. AKADEMIENS HANDLINGAR. BAND 34. N:0 I. 21

the an^^les, all turned in an aii^le of 15° — 20° towards the longitudinal axis, thinner
and stronger intermingled. Terminal awns very long, stronger than the others, angular,
with spirally arranged small spines, which become stronger towards the distal end.
Endocysts in tlic middle of the cellules, biconvex, covered with numerous, long bristles.

Longitudinal axis 0,oi2 to 0,02s. Sagittal axis 0,o2 to 0,025. Endocysts 0,oo9 to 0,oi2
long. Their sagittal axis 0,o2 to 0,025 millim. This species was found in March 1898 at
7°N., ^:rW. (Temperature 25,y.)

This species is well distinguished from all known forms by the absence of foramina,
by tlic direction of tlie awns bv the endocysts and the size. In the absence of foramina
and the direction of the awns it reminds of the very small form, which I have named
C. mbtilis (Bih. till. Kongl. Sv. Vet.-Akad. Handl., Vol. XXIII 3, n:o 5, fig. 8). Another
form without foramina I found in plankton from the Caspian Sea.

Chietoceros Ostenfeldii. N. Sp.

Plate VIII. Fig. 19.

Chains flexible, witli large oval foramina, as large as the cellules. Cellules thin-
walled, with concave valves, somewhat longer than broad. Awns thread-like, short.
Terminal set;e stronger than the others. Cell-contents (as far as could be ascertained on
alcohol-preserved specimens) with one chromatophore along the wall of the zone.

Longitudinal axis of the cellules 0,oi. Sagittal axis 0,oo7 millim.

This form has a considerable resemblance to C. laciniosus Schutt, but is much
more delicate and has a single chromatophore. It lias been distinguished by Ostenfelu
.(lagttagelser over overfladsvandets temperatur, saltholdighed og plankton, in 1898) as
»C'. laciniosus ojf'.i^

It was observed in April 1898 abundantly at 49 — 48 N., I9°— 29°\V., rarer in
the Irminger Sea and the FSrOe Channel, but became there common in May. Later it
was seen only rarely, but in August it was found abundantly between Iceland and
Greenland.

Dactjiiosoleii hyaliuiis. N. Sp.
riatc VIII. Fig. 33.

Cellules cylindrical, 1' 2 to 2 times longer than broad, tirnjly iniited into confervoid
threads. Valves circular flat, without any visible structure and Avith simple, not crenulate
margins. Zone with numerous transvei-se rings, 2 in O.oi millim., not distinctly punctate.
Chromatophores small. Length of the cellules (),ot! to 0,on, their diameter 0,o-t millim.

This species was found from February to June 1898 in the region of the New-
foundland Banks, associated with species belonging to styli-plankton. It reappeared on
the same area in November. Temperature 14,4, mean of 32 obs., max. 20, min 8. Sali-
nity 3.J, mean df 27 ol)s., max. 3(i,4ii, min. 32,62.

22 r. T. CLEVK, NOTES UN SURIE ATLANTIC I'LANKTON-OHGANISMS.

Skeletouema tropicuni. N. Sp.
riate VIII. Fig. 30, 31.

This species differs from S. costatiim in its larger size and numerous, closer peri-
pherical processes. Sagittal axis 0,oi5 to 0,o38, longitudinal axis 0,oi millini. Processes
7 to 9 in 0,01 millim., their length 0,oi to 0,o2 millim. 1 found this species in samples
from the coasts of S. America, 29° S. and 6°— 10°N. Temperature 23,8 to 27,2. Salinity
from 34,53 to 36,oi. Evidently a tropical neritic form.

Thalasslosira condensata. N. Sp.
riatc VIII. Fig. 12, 13.

Cellules very thin-walled, short, cylindrical, united by a single central short slim-
thread to somewhat rigid chains. Valve orbicular with a central pore and a marginal
circlet of close small protuberances, about 7 in 0,oi millim., but else without any visible
structure (on ignited specimens). Zone with numerous rings. Chromatophores small and
rounded, along tho interior wall of the cellule. Length 0,02 to 0,03, diameter 0,o25 to 0,03
millim.

The membrane is so little silicious that it, on drying, becomes deformed.

This species was found in October 1899 at Plymouth together with several arctic
forms.

V. T. OLEVE, NOTES ON SOME ATLANTIC PLANICTON-OIiGANISMS.

Plate 1.

Via.. 1 — 7. Acartia macropus Cl.

» 1. Outline of the male, dorsal X 85.

» 2. Outline of the female, dorsal X 85.

» ?>. Left anterior antenna of the male X 170.

s 4. Right anterior antenna of the male X 170.

» 5. Fifth foot-pair of the male X 170.

i> C. Fifth foot of the female X 300.

» 7. Head of the male, lateral X 170.

» 8 — 11. Cori/cfms loni/iraiiJis DANA, male.

» 8. Outline, dorsal X 85.

» 9. Outline, lateral X 85.

? 10. Abdomen and furca, dorsal X 170.

» 11. Posterior antenna X 500.

Koncrl. Vet. Akad. Handl. Bd. 34-. N2 1.

PL I.

liih "W ScKLachter StocHiolm

K. Sv. Vet. Aliud. llanill Bnnd M. N:o 1.

KONGL. SV. VET. AKADEMIKNS HANDLINGAR. BAND 34. N:0 I.

Plate 11.

Enchirella rostrata Claus. ; male.

Fig. 1. Outline, lateral X 40.

» 2. Fifth foot-pair X 85.

» 3. The same from a young specimen ... • X 85.

» 4. Abdomen, dorsiil X 85.

» 5. Mandible X 170.

» G. Second maxillipede X 170.

» 7. Posterior antenna X 170.

» 8. First foot X 170.

» 9. Second foot X 170.

> 10. Third foot X 170.

> 11. Fourth foot, B. I and B.2, Ri X 170.

» 12. End of the left first antenna X 85.

l.Bd. 34-. m 1.

PL n.

lith "W. Scblach.teT StodttLoIro.

p. T. CLEVE, NOTES ON SOME ATLANTIC PLANKTON-ORGANISMS.

Fig.

1 — 11.

»

1.

''1

2.

s

3.

»

4.

»

6.

»

t).

»

7.

»

8.

»

9.

»

10.

»

11.

«

12.

»

la.

i)

14, 15.

»

16.

»

17.

»

18

Plate III.

Onccea suhtilis GlESBR. Male.

Outline, dorsal X 170.

Outline, lateral X 170.

Left anterior antenna X 500.

Right anterior antenna X 500.

Abdomen and furca, dorsal X 300.

Furca, dorsal X 500.

.\bdomen and furca, lateral X 300.

Posterior maxillipede X 500.

Posterior antenna X 600.

Second foot X 500.

Fourth foot X 500.

Antlioci/rtiitiii untlietiiis Hkl.? X 500.

Sethoconus crinitus Cl. . X 500.

Challengeron brevispina Cl X 600.

Euphyselta pusilla Cl X 500.

Sperinatogoniu aiitiqua Leud. Foktm ■ X 500.

Sperm, ant. central cajisuleC!'), treated with soda X 600-

Vet. Akad, Handl. Ed. 34-. N2 1.

PI nr.

1 Cle"^re

lifh W. Schlachter Stocicholit:.

KONGL. SV. VET. AKADEMIENS HANDLINGAK. BAND 34. N:0 I.

Plate IV.

Fig. 1. Qiiadnlonche crux Cl X 500.

» 2, 3. Lainprcniiitra eroaa Cl X 500.

J 4. PsUuinelisaa loiKjispina Cl X 500.

» 5. Dictyocerus neglectum C'L X 500.

» 6. Sethoc'/rtis pi/rum CL X 500.

>, 7. Theoci/rtis turris Cl X 500.

» 8. Thcoconas junonis Hkl. affin X 500.

» it. Clathrocaidum minutnm Cl X 500.

» 10. Dictyoccphalus cijlindricus C'L X .jOO.

» 11. Tlieocijrtis uculeata Cl X 500.

Kongl. Vet. Akad. Handl. Bd, 34-. N2 1.

PL iv;

D-l

lifh W. Schlachter StocHiolm

p. T. CLEVE, NOTES ON SOME ATLANTIC PLANKTON-ORGANISMS.

Plate V.

Fig. 1. Amphihymenimn elegans Cl ^ ^*^*^-

» 2. ActinommaCh sol. Cl • X •'^*"^-

» 3. Actinosphara trichophora Cl ^ "'''^•^•

» 4. Halioiiima irregulare Cl '^ ^^'^•

s 5. Haliomma echiuosphcera C'L ^ ^^^•

» 0. Ilexacontium setosuin Hkl.? ^ ^*^'^-

i 7. Haliomma spinnlosuiiu with two exterior shells X 300.

ret. Afed Handl.

?1.V-

i>rt- p.

Ijth 'W Scfciachier StocMiolni

K. Sv. Vet. Aku.l. Iluii.ll. Hand 34. i\:o 1.

KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 34. N:0 I.

Plate yi.

Fig. 1. He.xastylus nohilis Cl ^ ''^0-

» 2. Heliosphcvra minuta Cl ^ '^""•

» 3. Tri/paiiospltcera hrachysiphon Gl ^ •^^'^'•

» 4. Hexaconthnn hostile Cl ^ ^'^"^•

» 5. Hexaconlium urmatum CL ^ ^^^-

I^oiiQl. Vet. /;

dl. Bd. 34-. :

P1;Y[.

-tST StockhohTi.

1'. T. CLEVE, NOTES ON SOME ATLANTIC PLANKTON-ORGANISMS.

Plate VII.

Fig. 1. Ceratium ranipes Cl X 250.

s 2. C. curoicorne V. Daday X 250.

» 3. C (tripos var.?) arietiuntn Cl X 250.

> 4. C. (tripos var.?) volans Cl X 250.

J. 5. C. (tripos var.?) vultur Cl X 250.

6, 7. C. (tripos var.?) azoricum Cl X 250.

8, 0. C. reflexion Cl X 250.

» 10. C. contortnm GOURRBT X 250.

11. C. (tnpos var.?) arnuatuni GoURRBT X 250.

5. 12. C. (tripos var.?) flagelliferum Cl X 250.

» 13. C. belone Cl X 250.

■', 14. C. parado.vides Cl X 250.

» 15, 16. Peridlnhim elegans Cl X 250.

» 17, 18. F. oceanicuni Vanhoffen X 250.

s 19,20. P. diabolus Cl X 250.

» 21, 22. P pallidum OSTENF X 250.

» 23. Pyroryslis hamulus Cl X 250.

» 24. Xanthidium, paucispinosnm Cl X 150.

» 25. Clicetoceros longisetus Cl., sterile chain X 500.

» 2(1,27. C. longisetus Cl.; with endocysts X 500.

28,29. C. longisetus Cl.; terminal setse X 1000.

» 30, 31. Skeletoneina tropicum Cl X 500.

» 32. Asterivnella notata Grun X 250.

» 33. Dactyliosolen hyalinus Cl X 250.

'.'et. Akad. Hand:

PI. vir.

KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 34. N:0 I.

Plate YIII.

Fit;. 1, 2. Hyalophysa di'UcaUda Cl X 500.

» 3. Dinophysis Vanhoffenii OSTENF X 500.

» 4. Steiniella{?) punctata Cl X 500.

■> 5. Pe7'idiinu)n exiguwn Cl X 500.

» 6. Asteromphaltis heptuctis Ralfs X 1000.

» 1. A. atlanticus Cl. from Portugal X 1000.

» 8, 9. A. atlanticus Cl. from N. Atlantic X 1000.

» 10, 11. Phalacroma minutuni CL X 500.

•i 12. T/ialassiosira condensata CL.; a chain X 500.

» 13. Th. condensata Cl. ; a valve, ignited X 1000.

» 14. Ceratiuni{?) hyperboreuin Cl X 500.

5. 15. Pterosjihwru Mobii J0RUENSEN X 500.

» 16. Cha'toceros dificilis Cl., sterile chain X 1000.

» 17. The same, with endocysts X 1000.

» 18. The same, eudocysts, from above and from the side X 1000.

» 19. Chceloceros Ostenfeldii Cl X 1000.

KoiigI. Ve

PI. viti.

m^-

\xMInX