FREES INSTITUTE. OF SCIENCE 
ON THE LIFE HISTORY OF AN ECONOMIC CUTTLEFISH OF JAPAN 
The buccal membrane of the female has in its tissue about thirty 
seminal receptacles arranged in a circle (fig. 3). In the mated female 
the receptacles appear opaque white in color, being full of spermatozoa 
which have undoubtedly penetrated into the tis- 
sue, being set free from the spermatophores on the 
membrane. It is noteworthy that many females 
examined had an immature ovary, though they are 
provided with spermatozoa in their receptacles. 
The spermatozoa may, of course, remain alive in the 
receptacles. It follows that the pairing season does 
not necessarily exactly coincide with the spawning 
season. I may be permitted to add that the above me. 3: 
mentioned position of the receptacles is not without Inner view of the buccal 
- membrane of a mated fe- 
significance but stands in an important connection male WNibanzurwmé, nat. 
size. bm, Buccal mem- 
with the spawning habit of the animal,* a subject brane; ii, inner lip; ol, 
é 2 outer lip; sr, seminal re- 
to which I will return later (see pp. 13, 14). ceptacle. 
MATURATION OF FEMALE GENITAL ORGANS AND SPAWNING 
SEASON 
The nidamental glands of the female make their first appearance in 
females of about 150 mm. mantle length and reach a size of about 20 mm. in 
those of about 200 mm. mantle length, while in fully mature females, which 
are above 280 mm. mantle length, the glands attain a length of about 180 mm. 
and a weight of about 60 grams, being quite as large and heavy as in the littoral 
cephalopods like the Loliginidae (fig. 4). 
The ovary is still immature in the females below 200 mm. in mantle length. 
In the fully mature females referred to above, the ovary is about 48 grams in 
weight, occupying the posterior half of the mantle, and is filled up with the 
mature eggs only. The oviducts of these females, full of mature eggs, weigh 
about 30 grams each. 
Fully mature females, such as above mentioned, are very rare. I have 
obtained them in the Bay of Toyama in spring and in Hokkaid6 in summer. 
* The Loliginidae and Sepiidae are provided with a pair of dendritic or racemose seminal 
receptacles in the tissue of the buccal membrane, in a similar way to that just mentioned, and 
deposit eggs fixed on the sea bottom or something found there. 
