436 PERCY SLADEN TRUST EXPEDITION 



The male genitalia have been already described by Marchand (13) and do not appear 

 to differ in any important respects from those of Polypus. 



The female genitalia in this species appear to differ from those of Polypus somewhat 

 (fig. 2). The oviducts leave the ovary in the form of broad, strap-like ducts, narrow- 

 ing down as they approach the oviducal glands. The latter are relatively very large. The 

 anterior portions of the oviducts do not again contract on quitting the oviducal glands but 

 continue as stout muscular tubes to the oviducal aperture which is situated upon a round 

 elevated papilla of characteristic shape surmounted by a tuft of small (possibly glandular) 

 lobes which surround the aperture. 



Coelom and coelomic organs. The limits of the kidney are shewn in fig. 2. It is 

 a voluminous organ and possesses extensive glandular bodies. It is divided by the afferent 

 and efferent branchial vessels into three portions, the long axes of which are transverse in two 

 cases, antero-posterior in the third. The latter is small and contains the i-eno-pericardial 

 orifice which is situated at a veiy short distance from the entrance to the renal orifice ; 

 while the former are extensive and ramify among the digestive organs in such a way as to 

 make it difficult to follow them. 



kidne 



pericardium -z^—. 



app'nd'x of /sicl, 

 branchial heart i 



pericardium 



gonad ^xi^HlH mB' 



A B C 



Fig. 3. A. Decapod. B. Polypus. C. Scaeurgus. 



The so-called aquiferous dAict leaves the capsule of the ovary from a very anterior 

 position and running backwards comes into close contact with the pericardium in the 

 external tissues of which it runs as a fine fibrous strand gradually diminishing in size until 

 it entirely vanishes near the apex of the pericai-dium. Very careful dissection of both sides 

 failed to reveal any opening of this duct into the pericardium. If this observation should 

 be confirmed by future investigators, it will be permissible to suppose that morphologically 

 Scaeurgus carries us a step further than Polypus in the obliteration of the coelomic cavity, 

 and would represent the third stage in the annexed diagram in which the gradual reduction 

 of the coelomic cavity of the Cephalopoda is illustrated (Text-fig. 3). 



This process of separation of the gonad from the remnant of the coelom would be 

 finally completed by the condition observed in Argonauta and Philonexis in which the 

 aquiferous canals are suppressed altogether (Pelseneer (14)). 



It is necessary to emphasize the fact that these observations are founded upon dis- 

 section of a single specimen and that due caution is necessary in employing them for any 

 generalization. 



The anus is in the form of a transverse slit at the lateral extremities of which are 

 found pedunculate flaps of skin which apparently function as valves and are capable of being 

 folded over the aperture. 



The heart (fig. 2 a) is asymmetrical, rectangular on the left side and drawn out by the 



