276 AUSTBALIAN MALACOSTEAGA. 



kinds, the first five pairs foliaoeous and branchial in function, 

 the sixth pair operculiform, lamellate or styliform. No caudal 

 appendages. 



Sub-Tribe Idoteidea. 



Body oblong-oval, or linear in form. Posterior pair of 

 abdominal appendages enlarged, operculiform, closing over the 

 other (branchial) abdominal appendages. [_M.~\ 



Family I. IDOTEIDM. 

 Legs all similar, sub-prehensile, or adapted for walking. 



Genus Idotea, Eabr. 



Body elongated. Head quadrilateral, broader than long. 

 Eyes placed laterally. External antenna much longer than the 

 internal, and terminating in a multi-articulate flagellum. Maxil- 

 lipedes very large. Seven segments of the body all nearly of 

 the same shape and size. Abdomen with several of the seven 

 segments short, usually more or less coalescent, the terminal 

 segment very large, its appendages greatly developed, covering 

 the whole inferior surface of the abdomen, and closing like doors 

 over the branchial appendages. [Jf.] 



478. Idotea striota. 



Idotea striota, Dana, U.S. Explor. Exped., Crust., Vol. ii., 

 p. 704, pi. xlvi., fig. 7. 



Narrow, front excavate, head a little transverse. Epimerals 

 very small. Outer antennae about half as long as body, flagellum 

 shorter than the base, ten-jointed, naked. Inner antennae hardly 

 reaching to penultimate basal joint of outer pair. Abdomen 

 narrow oblong (length more than twice the breadth), triangulate 

 at extremity and subacute, lateral margins a little excavate or 

 concave. Eeet sparingly hirsute below. [J>.] 



New South Wales. 



479. Idotea caudaouta. A.M. 

 Idotea caudaouta, Haswell, 1. c, Vol. vi., p. 1, pi. iv., fig. 4. 

 Length of body about three and two-thirds the greatest breadth. 



Head nearly twice as broad as long, front deeply concave. 



