Vlll 



Fig. 23.- 

 Fig. 24.- 



Fig. 25.- 

 Fig. 26.- 



Fig. 27.— 



List of Text-figures 



Fig. 38.- 



Fig. 39.- 

 Fig. 40.- 

 Fig. 41.- 

 Fig. 42.- 



Fig. 43.- 

 Fig. 44.- 



Fig. 45.- 

 Fig. 46.- 

 Fig. 47.- 

 Fig. 48.- 

 Fig. 49.- 

 Fig. 50.- 



Figs. 51, 



Figs. 53, 



-A. glacialis. Crotchets, in three phases of growth . 



-A. 2iusilla. Crotchets from the type specimen, and from 

 specimens 17 and 160 mm. long ...... 



-A. cristata. First crotchet of a larva '25 mm. long 



,, Crotchets from specimens 48, 130, 250 and 



330 mm. long ......... 



A. loveni. Crotchet from the type specimen, and from a 

 specimen from Saldanha Bay ...... 



-A. ecaudata. Crotchet from a post-larval specimen, 8 mm. long 



- ,, Dorsal and ventral crotchets of a neuropodimn 



from a specimen 200 mm. long ..... 



-A. branchialis. Crotchet from a specimen 230 mm. long 



-^4. marina (from Wood's Holl). Dorsal axis of gill 



-A. pusilla (from Unalaska). Dorsal axis of gill 



34. — A. glacialis. Gills ...... 



-.4 brancJualis. Gill ....... 



-A. ecaudata. Dorsal gill-stem ..... 



-A. marina. Statoliths, and cuticular lining of statocysts of 

 specimens from Jersey and Trieste .... 



-A. assimilis var. affinis. Statoliths, and cuticular lining of 

 statocysts of specimens from Otago Harbour and the Falkland 

 Islands ......... 



-A. glacialis. Statoliths, and cuticular lining of statocyst 



-A. cristata. Statolith, and cuticular lining of statocyst . 



-A. branchialis. Statoliths, and cuticular lining of statocj^st 



-A. marina. Eipe spermatozoon and ripe ovum; A. bran 

 chialis, ripe ovum .... . . 



-A. loveni. Anterior end, dorsal aspect .... 



,, Type specimen ; a portion of the nineteenth 



chaetiferoiTs segment, the extra (twentieth) segment and 

 notopodium, and a portion of the tail ..... 



-A. cristata. Anterior end, dorsal aspect .... 



-A. glacialis. Anterior end, dorsal aspect .... 



,, Diagram of a dissection of the anterior portion . 



-A.pusilla. Anterior end, dorsal aspect ..... 



,, Anterior aspect ....... 



,, Type specimen, I'ight aspect of tenth chaetiferous 



segment .......... 



52. — A. pusilla. Type specimen, antero-ventral and dorsal views 

 of the anterior end . 



54. — A ptisilla. Specimen from California, antero-ventral and 

 dorsal views of anterior end ....... 



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