NO. 14 MILLIPEDS OF WEST INDIES AND GUIANA LOOMIS 57 



laterad of the outer row of large tubercles has three lobes, of which 

 the outer one is much the largest, conspicuously elevated, and is close 

 to the posterior corner of the keel. Lateral keels not projecting as 

 far from the sides of the body as in P. crescentis and placed somewhat 

 higher on the side of the body. 



Last segment with the two dorsal tubercles narrower than those of 

 P. crescentis. 



Females with a definitely raised, back-curving crest on the ventral 

 side of the third segment in front, immediately behind the second pair 

 of legs. 



Just how this species differs from P. sequens (Chamberlin) is not 

 known, for aside from the characters of the gonopods, no characters 

 are mentioned for P. sequens that allow it to be distinguished from 

 the Haitian species. 



Family STIODESMIDAE 



HOMODESMUS PARVUS Chamberlin 



Homodcsmus partms Chamberlin, Bull. Mus. Comp. Zool., vol. 62, pp. 222, 223, 

 1918. 



A male, similar in all particulars to specimens of this species from 

 Haiti, was collected in the crater of the extinct volcano known as 

 " The Quill " near Orangetown, St. Eustatius, January 22, 1932. 



Chamberlin has reported this species from Puerto Rico. It is 

 abundant in Haiti, from which country it may have been dispersed to 

 these other islands in comparatively recent times, as it has not been 

 found there in numbers. 



GASATOMUS EMERSONI Chamberlin 



Plate 3, fig. 6 



Gasatomus cinersoni Chamberlin, Zoologica, New York Zool. Soc, vol. 3, pp. 

 417-419, 1923. 



A male was collected in the Maracas Valley, Trinidad, February 13, 

 1932. 



It coincides in all particulars with Chamberlin's description and 

 illustration except in size, for it is 6.5 mm long and 1.3 mm broad. 



The anterior legs and sterna show no secondary sexual modifica- 

 tions. The sterna behind the gonopods, however, are strongly elevated, 

 narrow, deeply depressed in each direction, and the posterior sternum 

 of each segment is produced behind on each side into a rounded lobe. 



The gonopods are somewhat of the type of those of Cynedesmus 

 simplex Loomis, but the inner piece of each is shorter, heavier, and 

 more simple. 



