NO. 14 MILLIPEDS OF WEST INDIES AND GUIANA LOOMIS 4I 



the anterior one heavy and definitely foHate near the apex, the pos- 

 terior branch slender, attenuated (fig. 20). 



Anterior male legs without lobes or other secondary specializations. 



The discovery of this tiny species was of particular interest be- 

 cause of its having only 18 segments, a condition never before ob- 

 served in the Merocheta, no mature member of which had previously 

 been found with more than 20 or less than 19 segments. 



Another closely related i8-segmented milliped was later found in 

 Cuba and given the name of Hexadesmiis lateridens.^ This species 

 is now known from Haiti, St. Kitts, and Carriacou of the- Grenadines. 



Fig. 20. — Agcnodesmus reticiilatus. Gonopods. 



With the exceptions of the Oniscomorpha, in which 13 segments 

 is the maximum, and the Limacomorpha with 20 or 21 segments, none 

 of the remaining orders of Chilocheta contains animals with so few 

 segments as in the Merocheta. In the Merocheta, species with only 

 19 segments are the exception rather than the rule, by far the largest 

 number having the full complement of 20 segments. In some of the 

 small forms, such as Brachydesmus and Bactrodcsmus, the possession 

 of only 19 segments is believed to be a depauperate condition, and 

 this view seems to be supported and supplemented by Ageiiodcsinits 

 and Hexadesntiis. 



Not only is A. reticiilatus nearly the shortest of all known millipeds, 

 but it is decidedly more slender and delicate than any other yet dis- 

 covered, the proportions of a polydesmid having been closely main- 

 tained in spite of the greatly reduced length. 



Type.— v. S.N. M. no. iioo. 



HEXADESMUS LATERIDENS Loomis 



He.radesmus latcridois Loomis, Bull. Mus. Comp. Zool., vol. 75, pp. 362, 363, 

 illus., 1933. 

 Four female specimens, two of which are young, were collected 

 beneath rocks on the grassy hills south of Basse Terre, St. Kitts, 



Bull. Mus. Comp. Zool., vol. 75, pp. 362, 363, illus., 1933. 



