250 " THETIS " SCIENTIFIC RESULTS. 



In working out the various species I have been much impressed 

 with the paucity of information relating to this important group. 

 Many structural features have been met with, regarding which 

 little or nothing has been recorded, and numerous little points of 

 generic or specific import have been a source of frequent delay. 



Adequate definitions of some of the genera are still required, 

 and the whole group is in great need of revision. As regards the 

 species herein described, I have attempted to supply full descrip- 

 tions of all the characters of importance, whether generic or 

 specific, hoping such will prove useful in any future revision of 

 the order. 



There are many characters presented by the various appendages 

 of the body which have been usually neglected in descriptions ; 

 some are of generic and others of specific import. Such, for 

 instance, as the number and relative length of the joints of the 

 flagellum ; the presence or absence of denticles on the spines 

 of the first maxillse. The pleopods are rarely described, yet they 

 afibrd some excellent and reliable characters : a glance at some 

 of the descriptions and figures will sufiice to show how necessary 

 it is to examine these appendages. For example, the outer i*ami 

 of the first and second pairs of pleopods in Zuzara emarginata 

 are armed on their outer distal margin with a series of spines, 

 thus furnishing a character which alone would be almost sufficient 

 to identify the species. The uropods are generally well described, 

 but one feature, namely, the opposed or folding condition of the 

 branches is frequently neglected. In the genus Cymodoce the 

 branches are stated to be opposed or imperfectly folding. I have 

 met with two species, namely, C. aculeata and C. convexa, in 

 which the branches are completely folding, and a third, C. 

 tuberculosa, has the branches opposed. 



Family SPH^ROMID^. 



SPH^ROMA, Latreille. 

 SPH^ROMA AUSTRALIS, sp. nov. 



(Figs. Ua-h.) 

 Station 19. 



Body smooth, convex, about twice as long as broad, slightly 

 increasing in width posteriorly, cephalon not quite equal in 



