5o6 



PYCNOGONIDA 



In Avimothea and its allies they are extremely rudimentary 

 in the adult, being reduced to tiny knobs in Tanystylum and 



A B C D 



Fig. 266. — A, B, Chelophores of Ascorhynchus ahyssi, G.O.S. A, Young ; B, adult. 



(After Sars.) C, Anterior portion of Avimothea Mspida, Hodge, Jersey: late 



larval stage {=Ache!ia longipes, Hodge), showing complete chelae. D, Chela of 

 Eurycide hispida, Kr. 



Trygaeus, and present as small two-jointed appendages in Armno- 

 thea ; in this last, if not in the others also, they are present in 

 complete chelate form in the later larval stages. 



In Eurycide, Ascorhynchus, and Barana they are usually less 

 atrophied, l)ut yet comparatively small and with imperfect chelae, 

 while in some Ascorhynchi {A. miimtus, Hoek) they are reduced 

 to stumps. 



In Pallenopsis the scape of the chelophore consists of two 

 joints, as also in Decolojwda and some Ascorhynclius : in Nyniflum,, 



Fio. 267. — Chelae of species of Nymphonidae : A, Nym.phon brevirostre, Hodge ; B, 

 Boreonym2}hon rohustum. Bell ; C, Ohaetonymphon macronyx, G.O.S. ; D, Xymphon 

 elegans, Hansen. 



FhoxicMlidiutn, Pallene, and Cordylocliele of one only ; in all 



"furnished with a pair of di.stinctly tliree-jointed mandibles; and the .specimen 

 was the largest of the three obtained." 



