518 MAYNAKD M. METO ALF, 



ganglion, and the funnel receives its innervating fibres from the base 

 of the right anterior siphonal nerve, while the antero-ventral nerve 

 just described has no connection with either funnel or duct, I can 

 suggest only that the antero-ventral nerve in the Cionas innervates 

 both the ciliated funnel and the sides of the dorsal lamina, while 

 in the Polycarpas the two sets of fibres leave the brain at different 

 points and run in two separate bundles to their respective destinations. 

 Such a difference should not surprise us, for even closely related 

 forms differ greatly in the number of nerve trunks by which homo- 

 logous fibres arise from the brain. For example, the siphonal nerves 

 may arise from the brain by a single pair of large cords in front 

 and behind, or the fibres having the same ultimate distribution may 

 leave the brain in numerous nerve trunks. 



The Styelinae in general. 



The Styelinae agree with the BoUeniinae and the Cynthiinae in 

 the dorsal position of the neural gland, the gangliated character of 

 the rapheal nerve, the fusion of ganglion and gland, and the dextral 

 asymmetry of the ciliated funnel and of the duct of the neural gland. 



The Polycarpas differ from the Styelas in having merely a rudi- 

 mentary rapheal duct. This contrast between the two genera is 

 similar to that between different species of CyntMa, some of which 

 have the rapheal duct well developed, while in others it is present 

 only as a rudiment. 



In the Polycarpas the rudimentary rapheal duct is in the median 

 plane, or nearly so, showing no sign of dextral asymmetry. The 

 cruciform arrangement of the ducts of the neural gland in the Poly- 

 carpas is in marked contrast to the condition in the Styelas. 



The secretion of the gland in the Styelinae is formed as in the 

 other groups by the disintegration of cells proliferated from its endo- 

 thelium. 



The Molgulidae. 

 Under this family I shall include descriptions of Molgida man- 

 hattensis Verrill, Molgula arenicola (?), Eugyra pilularis Verhill 

 and Herdmania hostrichohranchus^). 



1) In Section VIII of this paper I will refer to the confusion 

 that has arisen between Molgula manhattcnsis and "Bostrichobranchus 

 manhattensis" and will describe as Herdmania hosfrlchobranchus a form 

 which seems to be a new species. 



