448 



SUPPLEMENT. 



and situation ; it contains spermatozoa of different degrees of develop- 

 ment, and the excretory duct probably debouches into the Hectoco- 



tylus. The Hectocotylus is developed 

 in a coloured sac, which occupies the 

 place of the third arm of the left side ; 

 the sac is cleft by the motions of 

 the Hectocotylus, which extends itself, 

 whilst the sac becomes inverted and 

 forms the violet coloured capsule on 

 its back. The sac never contains more 

 than one Hectocotylus, which is at- 

 tached by its base, whilst the rest of 

 it is free and coiled up. It has no 

 enlargement like the male Tremoctopn^ 

 (PI. I. f. 3) ; the filiform appendage 

 proceeds from the smaller extremity, 

 and sometimes remains entangled in 

 the coloured cyst on the back of the 

 Hectocotylus, near its base. It has a 

 chain of nervous ganglia in its axis, 

 (like that in the arms of ordinary 

 cuttle-fish.) 



M. Verany of Genoa, found the 

 male of "Octopus carona" {Tremoc- 

 topus gramdosus, Cuv.) with the right 

 arm of the third jjair more developed 

 than the others, and bearing an oval 

 globe at its free extremity (Fig. 231, C.) 



Fig. 231 , Octopus carena ^ , Ver. 



A. Side view, shewing cyst in place 

 of third arm. 



B. Ventral side of an individual more 

 developed, with the Hectocotylus C. 



This abnormal arm, agreeing with the 

 Hectocotglus octopodis of Cuvier, was 

 found to be developed in a cyst (A.) 

 like that of the male Argonaut. 



The Lingual denti- 

 tion of the cuttle-fish, 

 as described by Loven, 

 is most like that of the 

 Fteropoda and nucleo- 

 hranchiata. The cen- 

 tral teeth are simple in 

 Sejna and Sepiola, tri- 

 cuspid in Loligo, and 

 denticulated in Eledone. The lateral teeth, or zmcini, are three on each 

 side, and mostly simple and claw-like. There were 50 rows of teeth in the 



232, Lingual teeth of Seqia officinalis (Cocken.) 



