514 
THE VOYAGE OF H.M.S. CHALLENGER. 
■ . oi:r but rarely, often two arc found closely apposed, but not uncommonly three, four, or 
even more an so placed. It is, perhaps, with Chivtoceros remotum, Cleve and Grunow 
[ -- C. jar, is -hia um, Castracane], the most characteristic species found on the surface. 
Tli Clietocerotuhe and Rhizosoleniae are abundantly represented in the surface waters, 
hut they an- only represented by the terminal calyptrae of the latter in the bottom ooze. 
M" the delicately curved, though often large, forms of Corethron , and the singular 
< ylindrical Dactyl iosoltm, have only been found in surface gatherings, whilst the 
n-mirkabh- Trachysphenia australis, Petit, var. antarctica (Schwarz) [ = Fragilarict 
L,Jnrctica , Castracane], which abounds iu the ooze, is much less common in the surface 
gatherings. Frustules of Coscinodisci and Actinocycli are also much less numerous in the 
u:: - g; therii.gs than in the ooze at the bottom, but nearly all the species are present 
in the superficial waters found in the ooze. 
Th. contents of the alimentary canals of several of the Echinoderms and Annelids 
v. r xamined with the view of ascertaining whether or not a predilection was exhibited 
by the animals for any particular species of Diatoms; it was found, however, that they 
made use of the ooze as a whole, in all probability taking in the immediate surface layer 
com :i nj pecimens recently fallen from the surface, which, doubtless, still contained 
- -me oi Lrauie matter. The tubes of the Annelids, and the test of the Foraminifera Rcophax 
m.nlult w, contained many of the large Coscinodisci , which would appear to have been to 
a greater extent selected than the others in the deposit. 
The form, which Count Castracane has indicated as “ Fragilaria ? an Terebraria f 
.ip., 1 may be regarded as the southern representative of Fragilaria oceanica , Cleve, from 
the Vr. tie Ocean, with which it shows in the general arrangement and character of the 
f nut k 1 . - a considerable amount of agreement. Among the Diatoms observed at this 
Si it n th ■ following h; ve been also recorded in the Arctic zone, a few of the species 
being almost cosmopolitan : — 
Xaticula vpera, Ehrenberg. 
Tnrrralium arrtieum, Brightwell. 
IUunmoUnta "ivjera, Brightwell. 
„ ttyli/ormu, Brightwcll. 
ChMioctan* (Uripum*, Cleve. 
„ atlanti^um, Cleve. 
Cv*rinndi*mM dtemems, var. polaris, Grunow. 
„ „ var. rrpleta, Grunow. 
Coscinod incus mbtilis, Ehrenberg, var. glacialis, 
Grunow. 
,, oculus-iridis , Ehrenberg. 
„ central) s, Ehrenberg. 
„ normanni, Gregory. 
„ kutzingii, A. Schmidt. 
„ escentricus, Ehrenberg. 
„ lineatun , Ehrenberg. 
Among the peculiarly Antarctic species 
following : — 
found at this Station may be noted the 
/'•*>■■ ' o ' ' tirur.t, Grunow. Trac/njttphciii'a aiutralis, Petit, var. antarctica 
Am i; rr/ra a).!- rUura, Grunow. (Schwarz) [ - Fragilaria antarctica, Castracane]. 
1 BoL Chall. Exp., part iv. p. 47, pi. xxv. fig. 1. 
