224 BULLETIN OF THE 



Fig. G. The same; dorsal view, pore open. 



a. mucus beads exuding. 



6. slit widely opened, tlie walls or lips rolled out. 



c. mucus accumulations. 

 Fig. H. The same ; lateral view, pore open. 

 Fig. I. The same as last. 

 J- ig. J. The same ; the internal shell plate. 



PLATE V. 



Figs. F, H, drawn by W. G. Binney ; A, C, D, by Arthur F. Gray ; B, E, G, I, 

 by T. D. A. Cockerell, of West Cliff, Caster Co., Colorado : all from life. 

 Fig. A. Ariolimax niger, fully extended. 



Fig. B. Ariolimax Hemphilli, var. maculatus, Cockerell; animal contracted in alcohol. 

 Fig. C. Ariolimax niger; the caudal mucus pore, twice the natural size, dorsal 

 view, the pore open. 



a. mucus exuding. 



b. b. ridges each side of slit or channel. 



c. mucus channel or pore. 



d. little channels conducting mucus from back of animal into channel c. 

 Fig. D. The same ; posterior view. 



Fig. E. Ariolimax Californicus, in motion, natural size. 

 Fig. F. Ariolimax Anderson/, restored from an alcoholic specimen. 

 Fig. G. Ariolimax Hvmphilli, in motion, with end of tail and pore. 

 Fig. H. Portion of genitalia of E. 



p. s. the penis sac. 



/. the flagellum. 



r. the retractor muscle. 



v. d. the vas deferens. 

 Fig. I. Ariolimax niger, partially extended. 



PLATE VI. 



Figures B, C, D, E, H, were drawn by A. H. Baldwin, the last from life, the 

 others from specimens preserved in spirits ; Figures F, G, by W. G. Binney, from 

 life ; A, from life, by Arthur F. Gray. 

 Fig. A. Ariolimax Col-imbianus, var. mamlatus, Cockerell, natural size ; from a 



specimen collected by Mr. Hemphill. 



Fig. B, C. Onchidium Flaridannm, three times natural size ; from type. 

 Fig. D, E. Onchidella Carpenteri, twice natural size. 

 Fig. F. Tebennnphorus WetJterbyi; from type. 



Fig. G. Portion of genitalia of A. 



p. s. the penis sac. 



r. the retractor of same. 



v. d. the vas deferens. 

 Fig. H. Tebennophorus Hemphilli ; from the type. 



