162 DIPLOPODA. 
its typical species; and Brélemann’s selection of L. sallet as the type is null and 
void. 
Of the five species originally referred to the genus, Saussure in 1860 eliminated 
granulosus by referring it to Fontaria, and javanus by referring it to Odontodesmus 
(Mém. Soc. Phys. Genéve, xv. pp. 323, 328), thus leaving the choice of type between 
subterraneus, carneus, and aztecus. But the selection has been still further narrowed 
by the relegation of aztecus to the genus Neoleptodesmus by Carl in 1903. Of the 
two remaining species, I propose to select carneus as the type, a species which has 
been retained in Leptodesmus by both Attems and Carl, the latter of whom has given 
figures and descriptions of the secondary sexual characters of the male. Judging from 
these characters, which I have verified by an examination of the two examples in the 
British Museum, Z. carneus appears to me to differ generically from all the allied 
forms below enumerated from Central America. It differs at least in characters 
analogous with and equivalent to those which form the basis of the generic distinctions 
drawn between such genera as Acutangulus, Attems, and Neoleptodesmus, Carl. 
In addition to the species assigned to it below, Dirhabdophalius contains several 
others, such as D. plataleus, Karsch, D.goudoti, Gervais, and others from South America. 
Brélemann speaks of this section as the ‘‘ Plataleus-group of Leptodesmus”; and 
since the genus Leptodesmus, in the wide sense admitted by this author, by Attems, 
and by Carl, contains heterogeneous elements, it appears to me expedient to give 
nominal generic recognition to the above-mentioned section, which contains a number 
of kindred forms with common characters readily capable of definition. ‘They all 
apparently differ from the true Leptodesmus, as exemplified by the type-species, 
L. carneus, Sauss., in having the terminal segment of the leg long, the penultimate 
segment short, in the absence of an arthrodial pad beneath the joint of these segments, 
in the much simpler structure of the phallopods, the more conical caudal process, in 
having the keels of the anterior four segments less expanded and less depressed, in 
colour, and in size. Leptodesmus carneus, which has been described by Saussure, 
Attems, and Carl, is a very large Polydesmoid from Bahia. It is rosy-red in colour 
and reaches a length, according to Saussure, of over 80 mm. For its general 
characters reference may be made to the works of those authors just quoted. It must 
be added, however, that Carl’s claim to have described Saussure’s original examples 
must be dismissed, for Saussure expressly stated that the type of the species from which 
his description and figure were taken was an immature male with undeveloped 
phallopods, whereas Carl described an adult male and female, and there is no evidence 
obtainable from the text of the origina! description that Saussure had more than the 
one example in his hands at the time. ‘The examples from Rio Janeiro that he and 
Humbert subsequently—that is to say, in 1872—assigned to this species were possibly 
