ON SOME POINTS IN THE ANATOMY OF SEFIA OFFICINALIS, L. 



By E. H. BufiNE, B.A., 

 Assistant in the Museum of the Eoyal College of Surgeons of England, 



Read li.th January, 1898. 

 I. The Relation of the Peeitoneal Sac to the Body-Catity. 



Grobben,^ in a paper on the renal and rej)roductive organs of the 

 Cephalopoda, calls attention to a curious peritoneal sac that surrounds 

 the middle region of the genital duct of the male cuttlefish {Sepia 

 officinalis, L.). It is true that Brock- was the original discoverer 

 of this sac, but his description of it is so short that in reality Grobhen 

 is the chief source of our knowledge upon the subject. 



The sac encloses the vesicula seminalis, prostate, and caecum, and 

 from near its anterior end sends forth a prolongation that encircles 

 the apex of Needham's pouch in a loose spiral ; it is an entirely 

 closed chamber, with the exception of a communication with the 

 genital duct by means of a short tube lying between the vesicula 

 seminalis and prostate. 



Grobben suggests, with regard to the morphology of this peritoneal 

 sac, that it is a portion of the body-cavity pinched off from the rest, 

 but connected with the exterior by the above-mentioned tube, which 

 he regards as the remains of a second vas deferens. He holds this 

 view for the two following reasons: — (1) The similarity of the 

 epithelium lining the sac to that of the general body-cavity, and 

 (2) the presence in Philonexis carence,^ of two vasa deferentia, both of 

 which open into the genital capsule (body- cavity). 



In several male specimens of Sepia officinalis, L./ that I have 

 dissected, the general anatomical features of the sac and surrounding 

 parts are exactly as described by Grobben, with the addition, however, 

 of what appears to be a very distinct rudiment of the lost connection 

 between the peritoneal sac and the body- cavity. The rudiment has 

 the following features : — Upon the left side of the body, close behind 

 the fold that imperfectly sej)arates the pericardial from the genital 

 division of the body-cavity, there arises from the latter a forwardly 

 directed peritoneal funnel. In form it resembles a cone some 10 mm. 



1 Grobben, " Morphologische Studien iiber den Ilarn und GescMecbtsapparat der 

 Cephalopoden " : Arb. Inst. Wien, torn, v (1884), p. 14. 



- Brock, " Ueber die Gescblechtsorgane der Cepbalopoden " : Zeitscbr. Wiss. 

 Zool., Bd. xxxii (1879), p. 16. 



■' According to W. E. Hoyle, tbis is a synonym for Ocythoe tuherculata, Eaf. : 

 Proc. Eoyal Pbys. Soc. Edinb., vol. ix (1888), p. 213. 



* Tbe property of tbe Eoyal College of Surgeons of England: No. 2,371, B, 

 Pbys. Series. 



