170 THE VOYAGE OF H.M.S. CHALLENGER. 



PLATE XLIV. 

 Psycheotrephes exigua, n. sp. 

 Fig. 1. View of the outwardly directed side of a tentacle. 



Scotoplanes mollis, Thdel. 

 „ 2. Processes of one of the dorsal ambulacra. 



Orphnurgtis asper, The'el. 

 „ 3. Terminal part of a tentacle. 



Scotoplanes murrayi, The'el. 

 ,, 4. Terminal part of a tentacle. 



Peniagone wyvillii, n. sp. 

 „ 5. Terminal part of a tentacle. 



Elpidia purpurea, n. sp. 

 ,, 6. Terminal part of a tentacle. 



Peniagone wyvillii, n. sp. 

 „ 7. Branch of the terminal part of a tentacle. 



Benthodytes typica, n. sp. 

 „ 8. A dorsal process retracted, a, canal which pierces the perisoma and com- 

 bines the dorsal process with one of the dorsal ambulacra. 



Scotoanassa diaphana, n. sp. 

 „ 9. Terminal part of a tentacle. 



Peniagone vitrea, n. sp. 

 ,, 10. Terminal part of a tentacle. 



Ilyodcemon maculatus, The'el. 

 „ 11. Terminal part of a tentacle showing branched canals which communicate with 

 the tentacular cavity and lie enclosed within the thick sole-like terminal 

 part. 



Scotoplanes globosa, Theel. 

 „ 12. Terminal part of a tentacle. 



Deima validum, Theel. 

 „ 13. Longitudinal section of the end-portion of a slightly retracted pedicel. 

 a, outer layer of the integument containing calcareous plates ; 



