WAA or sg 
G, M. Txuomson.—On the New Zealand Entomostraca, 251 
Genus Idotea, Fabr. 
Idotea, Miers’ Cat. N. Z. Crust., p. 91. 
Idotea lacustris, nov. sp. 
Body narrow-elliptical, little more than twice as long as broad. Front 
of head excavate, not toothed. First segment of thorax somewhat longer 
than those succeeding, which are subequal; epimeral pieces nearly square, 
the last three slightly produced posteriorly. 
Abdomen 3-jointed, terminal joint (formed of three coalescent segments) 
hardly narrowing to the rounded extremity. Inner antenne not half as 
long as base of the outer, 4-jointed, joints subequal. Outer antenna 
one third as long as the body, flagellum 9—11-jointed, with a dense fringe 
of very short sete on the outer margin. Colour dark gray, mottled with 
brown, with a darker median band extending from the head to near the 
extremity of the abdomen. Length :6 inch. 
In numerous females, an ineubatory pouch extended along the whole 
under surface of the thorax. The young animals, taken out of this sac, 
have their bodies somewhat elongated in shape, with all the segments 
developed, and appendages present, but having the outer antenne furnished 
with a flagellum of only one joint and a few short sete. 
Art. XXI.—On the New Zealand Entomostraea. By Gzoncz M. Taonson. 
(Read before the Otago Institute, 26th November, 1878.) i 
Plate XI. 
Tue study of the lower orders of Crustaceans is, as a rule, confined to a few 
specialists, hence it is only now and then that they form the subject of 
communications to societies. In regard to this colony, the fact is that till 
the publieation of Miers' Catalogue of the New Zealand Crustacea in the 
British Museum, our knowledge of the whole class was fragmentary and 
scattered throughout numerous works. Now, however, that all the infor- 
mation on the subject has been thus collected and published in a condensed 
form, it becomes more easy to fill up the existing gaps. 
The Entomostraca are an interesting and but little studied division of 
Crustaceans, and from their abundance are of considerable importance. 
The species enumerated here have been collected chiefly within a few miles 
of Dunedin, and the marine forms only between tide marks ; so that we are 
as yet only on the threshold of the subject. 
