REVIEW OF SPENGEL’S MONOGRAPH ON BALANOGLOSSUS. 399 
gonads send distinct branches into them. Central nervous 
system as in Pt, sarniensis. 
Pt. clavigera, very large genital wings converging in front, 
so as to cover front part of gill region ; the gonad branch which 
enters them is so large as to dwarf the ventral fork of the bifid 
gland from which it arises; central nervous system as in 
Pt. minuta, 
Pt. aurantiaca, very like foregoing, but the still stronger 
genital wings contain, besides the great branch from the 
ventral fork of primary gonad, several longitudinal rows of 
accessory gonads with independent openings. Fig. 10 shows 
the form of its collar skeleton. 
Pt. erythrza has immense genital wings, which completely 
hide the branchio-genital region, and extend in lesser develop- 
ment into front part of liver region. They, however, are 
not exactly equivalent to the genital wings of other 
species, since the lateral septa are inserted near their free 
edges. Hence they correspond chiefly to a comparatively 
narrow strip at the proximal end of the wings in other species. 
The outer gill-pores are elongated into vertical slits, 
and the ventral pocket of the proboscis cavity com- 
pletely hollows out the “tooth” ofthe skeleton, con- 
verting it into a thin-walled sac. 
Pt. bahamensis very closely resembles the foregoing 
species, but is very much smaller. 
Spengel is inclined to divide this genus into three sub- 
genera, viz. Ptychodera (sensu stricto), including Pt. 
minuta and sarmensis; Tauroglossus, including Pt. aperta, 
clavigera, aurantiaca; and Chlamydothorax, including 
Pt. erythea and bahamensis. 
The genus Schizocardium (fig. 7) was erected by Spengel 
for the reception of a common species uf the Gulf of Rio de 
Janeiro, of which he obtained numerous specimens and made 
a very complete study. A second species of the same genus is 
founded on a fragment dredged up off the coast of Peru. It 
agrees with Ptychodera in possessing synapticula 
inthe gill-skeleton, and liver saccules, but differs in 
