CRUSTACEA OF ISTEW ZEALAND. 227 



" Upper antennoB longer than the lower ; the peduncle moderately elongate. 



" Lower antenncB with a short flagellum. 



" First and second gnathopods with the hand small ; the second larger than the 

 first. 



" The third uropods with long rami, furnished on the margin with spines and plumose 

 setae, extendiny- beyond the rami of the two preceding pairs ; the inner ramus more or 

 less shorter than the outer. 



" Telson long, cleft to the base." 



This definition answers very well to include Gammarus fragilts, whicb is the only 

 species of the genus that I have had an opportunity of closely examining. 



Gammarus peagilis, Chilton. (PI. XXI. figs. 1-25.) 



Gammarus fragilis, Chiltou, New Zealand Journal of Science, vol. i. (January 1882) p. 14; id. 

 Transactions New Zealand Institute, vol. xiv. p. 179, plate ix. figs. 11 to 18; id. New Zealand 

 Journal of Science, vol. ii. (March 1884; p. 89 ; Thomson & Chilton, Transactions New Zealand 

 Institute, vol. xviii. p. 1 16 ; Moniez, " Faune des Eaux souterraines du Departement du Nord. &c./' 

 extrait de la Kcvuc Biologique du Nord de la France, tome i. (1888-89) p. 50; Wrzesniowski, "O 

 trzecb kielzach podziemnych," De tribus Crustaceis Amphipodis subterraueis, pp. 16,90; id. " Ueber 

 drei unterirdische Gammaridcn," Zcitsehrift fur wissenschai'tlichc Zoologie, L. 4, pp. 611, 698. 



Specific diagnosis. Eyes wanting. Body rather slender. Superior antennae somewhat 

 longer than the body ; flagellum much longer than peduncle, secondary containing from 

 five to nine joints. Peduncle of lower antennae longer than peduncle of upper ; flagellum 

 longer than peduncle. Gnathopoda subequal, moderately large, each with the propodos 

 ovate ; palm very oblique. Pii-st and second perseopoda rather short, slender ; last three 

 pairs of peroeopoda very long, the last (fifth) about as long as the body. Terminal 

 uropoda with the rami subequal, about twice as long as the peduncle, cylindrical, not 

 flattened or expanded. 



Colour. White, semi-transparent. 



Length of largest specimen 15 mm. 



Habitat. Eyreton, North Canterbury {Chilton), Leeston {B. M. Laing), Winchester, 

 South Canterbury (Z>. L. Inioood) : in wells. 



llcmarks. It will be seen from the following detailed description that this species is 

 a true Gammarus, and that in all generic characters it agrees very closely with 

 Gammarus neglectus as described by Sars. I have not attempted to compare G. fragilis 

 with the numerous other species of the genus akeady described. It appears to be well 

 characterized by the very long perseopoda. the want of eves, and the long cylindrical 

 rami of the terminal uropoda. 



Detailed Description. 



The body (PI. XXI. fig. 1) is smooth, rather slender ; the appendages are also very long 

 and somewhat slender. The coxae (side-plates) of the first four segments of the peraeon 

 are rather deep, though not so deep as their respective segments. The segments of the 



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