ACTINOPODOrS HOLOTHURIOIDEA. 191 



on the fact that the pedicels in preserved specimens are in more 

 than one row in some parts of the body length, this might be 

 put in the genus Ilyodœmon, but as the dorsal papillse are so 

 distinctly in one row, [ have placed it in Lcdmogone. ■ I agree 

 witli previous writers, like Sluitek, in thinking that the distinc- 

 tion can not be maintained between Ihjodœmon and Lcetmogone ; 

 and this species offers a strong argument in support of that 

 view. 



The species nearest to the present one is 11 ijodamon fimhr latus 

 Sluitee, but there are some important points of difference which ob- 

 lige us to separate the two species : (1) The size is very different ; 

 in /. ßmhriatu?, the smallest specimen measured 8 x 2.5 cm., while 

 in the present species the largest examined is 4.7x0.8 cm. The 

 small size, as I have stated above, is not due to the immaturity 

 of the specimens. Hence we must believe that there is a con- 

 siderable difference in the size of the two species. (2) In /. 

 fimhr latus, the dorsum is said to be hardly more vaulted than 

 the ventrum. In the new species, the dorsum is decidedly 

 vaulted, while the ventrum is fiat. (3) In /. jimbrlatus, the 

 papillœ are said to be smaller than the pedicels, as in so many 

 other species of Lcetmogons and» Ilyodœmon. In L. seJenkai, the 

 papillae are broader than the pedicels. (4) In I. fimhrlatus, each 

 of the two dorsal radii has a double row of papilla?. In L. 

 selenkal, there is only one row of papilhe on each ambulacrum, a 

 fact which induced me to place it in the genus Lcetmogone. (5) 

 In /. fimhrlatus, dorsum and ventrum are " hell-violett " while 

 pedicels and papilla) are somewhat darker rose-violet ; the end- 

 disks of both pedicels and tentacles, are said to be dark violet. 

 In L. selenkai, the perisome is transparent and colorless ; the 

 end-disks of the pedicels are hkewise colorless, but those of the 



