38 SEXUAL ORGANS. 



be startled by the sudden appearance of masses of daric color in 



the water, and in the confusion the cuttle makes his escape 



W. R. Hughes, in Nohire, ix, 363, J8T4. 



Dorsal aquiferous pores are found openino- upon the liead in 

 Artionauta and Tremoctopus: they communicate with large 

 internal cavities. In Ommastrephes and Tremoctopus anal pores, 

 with small cavities, are found on each side of the siphon; in 

 Onychoteuthis the^' are placed in advance of it ; in other genera 

 they are wanting. Tlie buccal region in Histioteuthis and Om- 

 mastrephes has four a([uiferous pores, and there are six of them 

 in Onyciioteuthis, in Sepia and in Loligo : the other genei'a want 

 them. Finally, there aie brachial pores situated near the bases 

 of the tentacular arms and between the third and fourth pairs of 

 sessile arms : in Sepia, Sepiola and Rossia they communicate 

 with the great cavities in which are lodged the tentacles when 

 contracted ; in Loligo the smaller cavity only sufHces to lodge a 

 portion of the tentacula, and in Histioteuthis, Ommastrephes 

 and Onychoteuthis the cavity is still more restricted, and only 

 occupies a part of tlie head anterior to the eyes : wanting in 

 other genera. . Tiiese poies are i)robably lubricative in function. 



Se.riial Orgavti. 



The sexes are distinct in the ceplialopoda and in some of the 

 genera at least, the female individual is tiie largest and readily 

 distinguisliable externally. The rtpioductive organs are lamellar 

 or branched; their cellular contents are metamorphosed into ova 

 or spermatozoa, which are attached to the wall of a chamber 

 communicating with tlie pallial cavity by one or two ducts, which, 

 in the female present glandular enlargements. Upon the walls 

 of the branchial cavity of the female two nidi mental glands are 

 developed ; besides, sometimes accessory glands, Avithin which is 

 secreted a viscid Huid which envelops tlie ova and aggregates 

 them into various forms, dilleriiig according to the genus. 



In the male the cases or spermatophores containing the sper- 

 matozoa are furnished by a i)rostatic gland. , These spermato- 

 phores, in the dibranchiata are ovate, cylindrical and narrow, 

 consisting of a thin case, ending sometimes in a filament at one 

 end ; at the other or thicker end is contained a sack full of 

 spermatozoa, to Avhich is attached an elastic spiral cord, coiled 



