BIHANG TILL K. SV. VET.-AKAD. HANDL. BAND 11. N:o 15. 37 
produced into two angulations, the anterior small the posterior 
long and broad. The laciniations of the following segments 
are "exactly like those of I. speciosa, but less sharp-pointed. 
The pleon is produced into one small median extension, on 
each side of which there are incisions for the insertion of 
the uropoda. The pleon is similar in shape to that in Ianira. 
Colour. ? 
Length. 10 mm. 
Hab. Off the east coast of Patagonia, Lat. 4791'6"S. 
Long. 63297" W, at a depth of 63 fathoms. 
Gen. XI. Mancasellus. 0O. HARGER. 
Syn. 1874. Asellopsis. O. HARGER. >On a new genus of Asel- 
lide». The American Jour- 
nal of Science and Arts. 
4 Third Series. Vol. 7, p- 601. 
1874. » » S. I. SMITH (and O. HARGER). »The 
Crustacea of the fresh wa- 
ters of The United States». 
Rep. of the U. 5. Commis- 
sioner of Fish and Fisheries. 
Part 2, p. 638. 
1876. Mancasellus. 2 >Description of Mancasellus 
brachyurus, a new fresh wa- 
ter Isopod>. The American 
Journal of Science and Arts. 
Third series. Vol. 11, p. 304. 
Diagn. Corpus ovatum, deplanatum. 
Caput non rostratrum. 
Oculi conspicui. 
Antenne primi paris quartam partem antennarum secundi paris 
2quantes, flagello multi-articulato instructze. 
Antenne secundi paris longitudine corporis breviores, flagello multi- 
articulato instruct2e. 
Mandibule palpo destitute. 
La era segmentorum pereii producta, leviter incisa. 
Pedes pereii primi paris cheliformes, dactylis simplicibus; pedes 
parium sequentium 2&2quales, dactylis pedunculatis, bi-ungni- 
culatis. 
fedes uri styliformes, ramis binis angustis. 
Th>3 body 1s elongate, linear, depressed, 
The head is quadrangular, without rostrum. 
Tre eyes are distinct. 
