438 GEOLOGICAL SURVEY OF THE TERRITORIES. 
nerves or the cesophageal commissure. Claus also likens the stalked 
eyes to those of Myside. In Nebalia no ears have been found. : 
In the digestive canal, says Claus, we have a quite specific peculi- 
arity, together with approximations sometimes to the Amphipoda and 
Isopoda, and sometimes to the Mysidcee and 
, Podophthalmata. The short up curved 
” esophagus leads into a stomach with a 
complicated chitinous armature, in which 
an anterior and a posterior division can 
be distinguished. While in form and rel- 
ative size of both parts there is a resem- 
blance to the stomach of -—Amphipoda, so 
we may also observe in the position and 
number of the chitinous plates of the ap- 
i Piece _ paratus for triturating the food a true re- 
Fina Oo OFM en Ot Drain of Neat Semblance to the Isopoda, but also to the 
more enlarged to show the ganglion cells. pylorie division of the stomach of the My- 
Tee sidxe, whose capacious and sack-like ex- 
panded cardiac division seems to correspond to the differently-formed 
cesophageal portion of Nebalia. The slender intestinal canal along its 
whole course is surrounded with a uniform layer of circular muscles, 
and on the inner side of the tunica propria is surrounded with a thick, 
fatty layer of epithelium; it reaches to the beginning of the last seg- 
ment, which is nearly filled by the muscular rectum (afterdarm). At 
the origin of the intestine (chylusdarm) arise two anteriorly and four 
(two larger than the others) posteriorly-directed liver-tubes; these four 
latter-named tubes or coeea are attached by a richly-developed fatty 
tissue of the serous membrane to the intestinal walls, and reach far 
into the abdomen. The two anteriorly-directed cceca reach to the anten- 
nal segment, and are frequently wholly enveloped by the fat corpuscles 
of their serous coat. (Compare our figure of N. bipes, Pl. XX XVII, 
fig. 6.) 
‘The two anterior biliary coeca manifestly correspond to those which 
we so often, though not always, meet with in Podophthalmatous larvee 
(Phyllosoma, Sergestes-larvee, &c.), but which, however, exist oniy in a 
rudimentary state in many Edriophthalma. The histological structure 
of the liver-tubes agrees closely with that of the intestine; the circular 
muscles still remain, though scattered and: absent at intervals. The 
epithelium eonsists of smaller and larger cells filled mostly with large, 
fat cells, whose secretions, like a fluid tinged yellowish, fills the often 
widely distended cavity of the canals. Now, arising in a remarkable 
way on the under (or lower, wnterer) side of the intestine are two long 
ascending appendicular tubes, for the most part embedded in the fat body, 
which is enveloped by fat cells. The hinder intestinal appendages of 
Nebalia, in which we could not detect the colored secretion of the liver- 
tubes, remind one of the so-called malpighian tubes of the Gammaride, 
which arise at the beginning of the much longer rectum which passes 
through the three terminal segments of the abdomen. In Nebalia the 
relatively short rectum, by means of the numerous muscular bands sus- 
pending it from the intestine, performs the movements so generally ob- 
served in Phyilopods, by which the water is drawn in in an almost ryth- 
mical manner and then expelled. The anus, concealed by two triangu- 
lar chitinous plates of the terminal segment, opens between two small 
lateral flaps, which closely resemble those in ‘the inner side of the furcal 
appendages of the Protozoéa larva of Penzus. 
‘‘Of the pair of tubular glands which serve in the body of Phyllopod 
