1941] 
Neiv Cuban M Wiped 
37 
Preanal scale rather thick, broadly rounded behind, with 
a tiny supplementary projection at middle of posterior 
margin. 
Gonopod as shown in figure a of the plate. 
Sternum between the third legs narrow, high, almost 
hemispherical and with a considerable number of erect setae ; 
sterna between the fourth and fifth legs higher and with 
more erect setae than the third sternum. 
Schizodira gen. nov. 
Type Stenonia maculata Bollman, Proc. U. S. Nat. Mus., 
Vol. 11, p. 336, 1888. 
Syn. Platyrachus? maculatus (Bollman) Chamberlin, Bull. 
Mus. Comp. Zool., Vol. 62, No. 5, p. 216, 1918. 
Review of the original description convinces me that this 
species cannot possibly belong in the Platyrhacidae where 
Bollman and subsequent writers placed it. Bollman com- 
pared maculata with Stenonia fimbriata (Peters) but it 
appears that either he never had seen Peters’ species or he 
misinterpreted the original description of it, for it is certain 
that fimbriata, made the genotype of Tirodesmus by Cook in 
Brandtia, p. 51, 1896, is not related generically, at least, to 
maculata. 
I know of no species of Platyrhacidae as small as macu- 
lata, and none of this family has an expanded, crenate, front 
margin on the first segment, completely hiding the head from 
above, nor does the body have a pronounced longitudinal 
median line. These characters, however, are found in the 
Chytodesmidae and Stiodesmidae but in the description of 
maculata there is given no character indicating in which of 
these families it should be placed. Nevertheless, Bollman’s 
inclusion of it in the genus Stenonia, which he later dis- 
tinguished in two keys on the position of the pores, allows 
the inference that the pores of maculata are on the dorsal 
surface, removed from the lateral margin of the keels, a 
character placing the species in the Chytodesmidae, rather 
than in the Stiodesmidae which has pores on special pro- 
cesses of the margins of the keels. As no other chytodesmid 
genus has a notch between the third and fourth crenation 
from the posterior corner of the first segment, the generic 
