Miscellaneous. ] 49 



M. de Filippi has not been more fortunate than his predecessors 

 in his search for the males of the Eleutherice. M. Krohn still re- 

 mains the only naturalist who has observed one. The ova are deve- 

 loped rapidly, not, as M. Krohn thinks, between the ectoderm and 

 the endoderm, but in a cavity everywhere bounded by the endoderm. 

 This cavity is at once an ovary and an incubatory pouch, from 

 which the embryos appear to issue only by the laceration of the body 

 and the consequent death of their parent. The sexual organs do 

 not exist throughout the year ; from the middle of April (when his 

 observations commenced) to the end of the first half of May the 

 author could not detect a trace of them. From this period all the 

 individuals, without exception, were provided with them. Towards 

 the beginning of June the Eleutherice, which had previously swarmed 

 in the aquaria, all disappeared. The ova, after undergoing a com- 

 plete segmentation, become transformed into embryos belonging to 

 the form of the ciliated Plamdce. 



The author cannot, as MM. Krohn and Gegenbaur have done, find 

 in the division of the arms of the Eleutherice a sufficient character for 

 the approximation of these Medusae to Cladonema in the family 

 Oceanidae. The differences in the structure of the umbrella, in the 

 mode of locomotion, and in the position of the sexual organs (which 

 in Cladonema, as in the other Oceanidse, originate from the v^all of 

 the gastric cavity) appear to be more important than the analogies. 

 The author therefore proposes the formation for the Eleutherice of a 

 separate family — that of the Creeping Medusae. — Memorie della R, 

 Accad. d. Sci. di Torino, serie 2. tom. xxiii.; Bibl, Univ. October 25, 

 1866, Bull. Sci. pp. 196-198. . 



On the Anatomical Arrangement of the Lymphatics in the Torpedos, 

 compared with that presented by those in the other Plagiostomi. 

 By C. Robin. 



Although the arrangement of the lymphatics in Fishes is of great 

 simplicity compared with that in other Vertebrata, it nevertheless 

 leaves several important points to be elucidated*. It has been in- 

 vestigated by several eminent anatomists ; but the want of clearness 

 in the descriptions of them in dogmatic works on comparative ana- 

 tomy shows that more than one of the questions relating to them 

 requires solution. 



The organs furnished with lymphatics in these animals are: — 



1, the digestive tube, from the end of the oesophagus to the cloaca ; 



2, the pancreas and its duct (the spleen is destitute of them); 



3, the hepatic ducts, the gall-bladder, and the ductus choledochus ; 



* *• In the class of Fishes the lymphatic system is still only very imper- 

 fectly known" (Milne-Edwards, Le9ons sur la Physiol, et I'Anat. Comp. 

 torn. iv. p. 471). Milne-Edwards divides the lymj)hatics into deep-seated, 

 or visceral, and superficial. The vessels which he, like Monro and other 

 authors, describes among the latter, are cutaneous venous networks and 

 their median, lateral, and subperitoneal collective sinuses. 



