90 



DR. C. COLLINGWOOD ON A NEW FORM 



On a new Form of Cephalopodous Ova. 

 By Cutheert Collingwood, M.A., F.L.S., &c. 



(Plate I.) 

 [Eead February 3, 1870.] 



The large grape-like masses which constitute the ova of the 

 common Cuttlefish {Sepia), are of so remarkable a form, and so 

 commonly met with, that they attracted attention very long since. 

 Aristotle, whose acquantance with the reproductive bodies of the 

 Tetrabranchiates was not far behind that of the present day, was 

 no stranger to these large and singularly formed bodies ; and 

 they are commonly taken as the type of the spawn of Cepha- 

 lopods. But the Ova of this group differ considerably in size 

 and appearance, as well as in the numbers produced by a single 

 individual. In the case of Sepia, nature seems to have taken 

 special care to preserve these important bodies, having encased 

 them in a flexible horny covering, prolonged at one extremity 

 into a kind of tendril or filament, which entwines round some 

 fixed object which serves an anchorage. In the Poulp {Octopus), 

 Aristotle informs us that a shell, or some such convenient nidus, 

 receives the eggs, which adhere to it and are thus in some de- 

 gree, at least, protected from injury. In Loligo, &c, great num- 

 bers of ova are produced : cylindrical sheaths of a gelatinous con- 

 sistence are formed, each about 4 inches long and about \ inch in 

 diameter, and tapering at the free ends, the opposite ends being 

 all attached to some foreign body by filamentary processes from 

 | an inch to an inch in length. In each of these radiating 

 bodies there may be 200 capsules, each of which contains from 

 30 to 40 minute spherical ova. In Sepioteuthis there appears 

 to exist an intermediate form of ova, which connects the ra- 

 diating sheaths of Loligo with the large capsular ova of Sepia. 

 The ova are (as in Loligo) spherical, and enveloped in sheaths ; 

 but, as in Sepia, these are fewer and longer ; while in the Di- 

 branchiates the ova occupy a considerable space at the bottom 

 of the shell, as, for example, in Argonauta. 



In none of these, however, which represent the characters of 

 of the Cephalopodous ova, as far as known, is there any approach 

 to the characters of a remarkable body which I recently dis- 

 covered in the Atlantic Ocean, the nature, however, of which 

 was incontestable. We were becalmed in lat. 37° N. and 



