A SQUID 123 



the spermatophores are formed ; then follows the tubular penis, 

 which forms the forward end of the tract and has already been 

 observed lying in the mantle cavity to the left of the rectum. 



Exercise 7. () Make a drawing of the male genital tract. 



Exercise 7. (//) Open the spermatophoric sac and look for 

 spermatophores ; they are slender, white objects about half 

 an inch long. Mount several on a slide and make a draw- 

 ing of one. 



The female. The single ovary, like the testis, is a large 

 elongated gland occupying the hinder end of the visceral mass 

 and surrounded by a capsule. The oviduct communicates with 

 this capsule ; it passes forward along the left side of the visceral 

 mass, its walls becoming thickened in its course to form the 

 oviducal gland, and opens into the mantle cavity by means of a 

 large thick-lipped aperture to the left of the rectum. 



Two pairs of prominent accessory glands are present in 

 the female, the large, white, finely striated nidamental glands, 

 which cover up most of the other organs of the visceral mass, 

 and beneath them the much smaller accessory nidamental glands, 

 which are pink-colored in life and lie to the right and left 

 of the rectum ; both pairs of glands open at their forward ends 

 into the mantle cavity. These glands secrete the egg-capsules 

 which protect the eggs after they are laid, and while develop- 

 ment is going on within them. 



Exercise 7. (c) Make a drawing of the female organs. 



The nervous system. In the position of the principal ganglia 

 the squid resembles the snail, but these ganglia are difficult to 

 observe in a dissection because they are compactly massed 

 together and are protected by a cartilaginous capsule which 

 forms a sort of skull. The cerebral or supraoesophageal ganglia 

 form a large mass above the oesophagus ; broad commissures 



