346 JOHNS HOPKINS UNIVERSITY MORPHOLOGICAL MONOGRAPHS. 



nerves seen in Salpa cordiformis-zonaria correspond probably to those 

 fibers that leave the single pair of large nerves found in Cyclosalpa pin- 

 nata and join the plexus above the funnel. In other species of salpa 

 these organs are developed to different degrees. (See Fig. 7, Plate LVI, 

 and Fig. 7, Plate LVII.) 



Lahille (10) has shown that a plexus of nerve cells and fibers is 

 present over the pharynx wall and innervates the sensory cells of the 

 lips. This manner of innervation is not, then, exceptional for salpa. 



SECTION III. The Anatomy and Development of the Subneural Gland in 

 Salpidce, with incidental remarks upon the Homology of the Nervous 

 System in different Groups of Tunicates. 1 



So far as I can learn, the ciliated funnel is the only organ in salpa 

 that has been regarded, up to the present time, as homologous with any 

 portion of the subneural gland of ascidians. This has been universally 

 regarded as homologous with the ciliated funnel of ascidians which 

 serves in most species as the orifice of the excretory duct from the gland 

 proper, and perhaps in some species as a sense organ also. There are 

 present in salpa certain other structures that I regard as homologous 

 with other portions of the subneural gland of ascidians, pyrosoma and 

 doliolum. Before entering on the description of the condition in the 

 adult salpas of different species I wish to review briefly the conditions 

 found in the other groups of the tunicates, and then to take up the 

 development of these organs in Cyclosalpa pinnata. After this a 

 description of the gland in other species of salpa will be more intelli- 

 gible. With this foundation we will then be able to discuss briefly 

 the homology of the structures described in the different groups. 



Among the ascidians clavelina, amaroecium, Phallusia mammillata 

 and Molgula ampulloides will serve as examples. 3 In clavelina the 

 ciliated funnel opens backward into a canal that lies upon the ventral 

 surface of the brain, between the brain and the well developed subneural 

 gland. This latter is traversed by small ramifying canals that open 



1 In a preliminary notice of this paper (12) I was led by a manuscript error to 

 describe as cloaca that part of the branchial chamber ventral to the ganglion. A 

 comparison of the adult condition with that found in the embryo leaves no doubt that 

 it is really part of the pharynx. 



2 The description of the subneural gland in clavelina and amarcecium is based 

 upon Miss Lilian Sheldon's paper (18). 



