28 



Guide to Crustacea. 



Table-case (Fig. 9). Lcptodora liindtii is the largest species of the Order. It 



^^- ^- is found chiefly in lakes, and its glassy transparency makes it a 



very heautiful object when alive. It is exceptional in the small 



size of the carapace, which does not enclose the body and serves 



only as a brood-pouch. 



Fig 



Dapliivia ptile.x. Female carrying eggs in the brood-chamber. 

 Enlarged. [Table-case No. 1.] 



Sub-class II.—OSTRACODA. 



The number of somites, as indicated by the appendages, is 

 smaller than in any other Crustacea, there being, at most, only 

 two pairs of trunk-limbs behind those belonging to the head- 

 region. The carapace forms a bivalved shell completely enclosing 

 the body and limbs. There is a large, and often leg-like, palp on 

 the mandible. The antennules and antennae are used for creep- 

 ing or swimming. 



