2S 
ON A NEW SPECIES OF ENTEROPNEUSTA, 
from its ventro-lateral region to the limiting membrane of the 
epidermis numerous radial fibres. The trunk coelom represented 
in the branchial region by the spaces situated laterally to the 
oesophagus is here considerably reduced and represented by 
irregular spaces. 
The lateral septa (figs. 22, 23, Is.) are related essentially as in 
the described Ptychodera species. In the middle of the genital 
region the septa are of considerable breadth, and pass between 
the dorsal corner of the gut and the submedian line, which is 
here situated at about the middle of the internal face of each of 
the genital wings (fig. 23, Is.). Anteriorly the point of attach- 
ment of the septum to the gut gradually passes medianly (fig. 22, 
Is.) until at the level of the last developing gill pocket it passes 
over to the skin, to which it is then attached at both ends. In 
the branchial region the ventral point of attachment of the 
septum gradually approaches the lateral, which always remains at 
the submedian line until the two unite. Posteriorly to the 
middle of the genital region the submedian line gradually passes 
down from the mid-region of the inner face of the genital wing, 
and takes a position close to its base, and at the same time the 
septa are reduced gradually in breadth and finally end with a free 
edge in the anterior portion of the hepatic region. The lateral 
septa thus separate off from the main trunk coelom two dorsal 
chambers which anteriorly end blindly in the posterior part of the 
branchial region, while posteriorly they communicate with the 
main trunk coelom by their narrow openings. These dorsal 
chambers Spengel regards as blind-sac-like outgrowths of the 
trunk coelom arising in the anterior part of the hepatic region. 
Gonads: The gonads begin in the "genital wings" immediately 
behind the posterior rim of the collar and continue for a con- 
siderable distance into the hepatic region. As distinguished from 
Pt. miuuta, in which the gonads are simple unbranched sacs, they 
are in this species, in correspondence with the greatly developed 
"genital wings," much branched, and are here more complexly 
branched than is usually the case in Pt. clavigera. As in these 
species, only primary gonads and primary genital pores exist. In 
