86 OR. W. E. COLLINGE ON THJl 



B. Terminal segment of metasome produced as a blunt spine. 

 a. Lateral cephalic lobes small. 



b. Frontal spines not on the margin S. nodulosa (Kroyer). 



b' . Frontal spines on the margin S. leevis, Benedict. 



Synidotea., Harger. 



17. Synidotea hirtipes (Milne-Edwards). (PI. 9. figs. 36, 37.) 



Idntea hirtipes, Milne-Edwards, Hist. Nat. Crust, vol. iii. (1840) p. 134 ; Krauss, 



Stidafrik. Crust. 1843, p. 61. 

 Edotia hirtipes, Miers, Journ. Linn. 8oc, Zool. vol. xvi. (1881) p. 68. 

 Synidotea hirtipes, Benedict, Proc. Acad. Nat. Sci. Philad. 1897, p. 403 ; Stebbing, Sth. 



Afr. Crust. 1902, pt. n. p. 60. 



Stebbing has described the oral appendages of this species in great detail. 

 Restates: "The first maxillae have the outer plate surmounted by ten or 

 sometimes eleven spines, some of which are denticulate, none very powerful. 

 The inner plate is narrow at both ends, and has at the apex only two setse, 

 which are rather long, and, as usual, setose. 



" The maxillipedes have the first joint short, the epipod nearly parallel- 

 sided, not reaching the apex of the process of the second joint, though 

 extending considerably beyond the first joint of the palp; its upper margin 

 slopes inward. The process of the second joint is shaped as commonly in the 

 Amphipoda Gammaridea, and similarly fringed with seta? on the inner and 

 apical margins, but here it is tied to its fellow, each member of the pair 

 carrying a strong spine-hook for grappling the other. The first joint of the 

 palp is small and rather obscure, the second is very large, widening distally, 

 its distal margin flatly rounded on the inner part and externally forming a 

 little free projection. The third joint is also very large, its inner margin 

 almost continuous with that of the preceding joint, feebly convex, fringed 

 with short spines, its outer margin strongly convex, fringed with setse-like 

 spines, some of which also stand out from the surface." 



The First Maxilla (PI. 9. fig. 36). — In none of the'specimens that I have 

 examined have there been more than ten spines on the outer lobe, in addition 

 to which there is a long setule set in a cup-shaped cavity on the ventral sur- 

 face of the lobe. In a like manner there are three setules on the ventral 

 surface of the narrow inner lobe, the tv\o setose spines of which are rather 

 longtr than in most species. 



The Maxillipede (PI. 9. fig. 37). — This appendage in the genus Synidotea 

 is characterized by the large size of the second and third lobes of the palp. 

 In S. hirtipes the two divisions of the coxopodite are small. The basipodite 

 has both its inner and outer margins almost straight, the posterior and 

 anterior ones slope outwards. The three-jointed palp is almost twice the 

 length of the inner margin of the basipodite. The first joint is small, the 



