360 LECTURE XXIV. 



with a glandular laminated outlet ; and there are two distinct laminated 

 nidamental glands on each side of its termination. In the Octopoda 

 there are two oviducts, which in the Octopus and Eledone are each 

 provided with a special glandular enlargement about the middle of 

 their course : but there are no detached nidamental glands. In the 

 Loligo there are two distinct convoluted oviducts, and two separate 

 nidamental glands. These glands in the Cuttle-fish rest upon a soft 

 parenchymatous body, of a bright orange colour : the corresponding 

 part is rose-coloured in the Sepiola: it is double in tiie Rossia and 

 tlie Calamaries : these bodies have no ducts, and appear to be the 

 analogues of the suprarenal bodies in the vertebrate animals. 



The ova when received in the membranous part of the oviduct, 

 consist of a deep yellow vitellus, enclosed in a delicate vitelline mem- 

 brane, and protected by a thin smooth shining chorion : they receive 

 additional layers of a thick albuminous matter from the gland of the 

 oviduct, which may be compared to the shell-secreting cavity in the 

 oviduct of the fowl. The ova are connected together in characteristic 

 clusters by the secretion of the superadded nidamental glands when 

 these are present. 



In the Argonaut the minute ova are appended by long filamentary 

 stalks to the cavity of the involuted spire of the shell where they are 

 hatched. The ova of the Calamary are enclosed in long gelatinous 

 cylindrical sheaths, and otfer a close analogy to the spermatophora in 

 the male. The ova of the Sepioteuthis are likewise enclosed in cylin- 

 drical sheaths ; but these are shorter, and contain fewer ova, than in the 

 Loligo. The eggs of the Cuttle-fish are of comparatively large size, 

 of an oval form, attenuated at the extremities, and each enveloped in 

 its proper horny covering, which is prolonged into a pedicle at one 

 extremity, and attached by it to some foreign body : numbers of these 

 ova are generally found clustered together, and they have commonly 

 received the name of sea-grapes. 



The early stages in the development of the Cephalopodous Mollusk 

 appear not to have been hitherto observed. The head can very soon 

 l.i8 ^#ffi^v. ^^ distinguished by the pigment of the rudi- 



. '/ / . mental eyes: the branchiae at their first ap- 



pearance project on each side of the pedicle 

 of the large yolk-bag, from the anterior and 

 lateral part of the unclosed abdomen, and 

 the embryo Cuttle-fish at this period mani- 

 fests the infero-branchiate type. The visceral 

 ^^^ sac is progressively enclosed by the advance- 



^(fflf ment of the pallial walls from behind forwards ; 



Embryo Sepia. tile pcdiclc of the yolk-bag {Jig. 138. c) pro- 



