84 E. A. ANDREWS. 



The spatula {Sj>) is very large and hollowed on the median face 

 to form a wide spoon. The canula (C) is sharp-pointed and 

 somewhat curved, with a horny tip that plainly shows the groove 

 running to it and opening by a hole. There is also a new out- 

 growth (Z) that has the form of the spatula of C. virilis but arises 

 from the external mass, half way between the origin of the spatula 

 and the tip of the canula. This new outgrowth we will call the 

 ligula. 



Cross-sections of this stylet (Fig. 12 at the level 12 of Fig. 11) 

 show the presence of a shelf that cuts off the bottom of the groove 

 as a tubule, similar to that in C. virilis. This shelf has the same 

 yellow, homogeneous appearance. This section shows the long 

 flat extension of the median mass that forms the base of the 

 spatula and the shelf at the bottom of the overhung groove. 



In the section (Fig. 13 at the level 13 of Fig. 1 1) we see the 

 orifice and in the median mass {M.in.) glands with one of the 

 tubules discharging through the exoskeleton into the groove. 



This specimen seems to have been about to shed, so that the 

 exoskeleton is represented rather schematically in the sections, as 

 it was broken or laminated. 



Turning now to the genus Astacus, to which all the European 

 crayfish belong, the process of sperm transfer is known only 

 from the brief accounts of Soubeiran (5), Chantran (6) and Hux- 

 ley (7). From them it appears that the males seize and turn the 

 females and mount them, but the subsequent stages differ from 

 those in Cambariis in the fact that there are neither hooks nor 

 annulus, and thus no transfer of sperm to any sperm pocket ; on 

 the contrary, the sperm passes out of the stylets onto the sternal 

 surface of the female in the form of spermatophores. These 

 subsequently liberate the sperm at the time of laying in some 

 unknown manner that Whitman (8) states was referred by 

 Leuckart to the compession of the walls of the spermatophores 

 and by Meyer to the action of the secretion that fastens the eggs. 

 That the same general method is followed by the Astacus of the 

 west coast of the United States seems undoubted from the simi- 

 larity in the anatomy of the organs concerned and from the fol- 

 lowing observations. 



Amongst female crayfish of the species A. Ie7iiiisculits, received 



