OOKINESIS IN LIMAX MAXIMUS. 385 



Fig. 4 illustrates part of a section of egg shown in Fig. 2, cut 

 in such a plane as to show the sperm nucleus near the periphery. 

 Drawn with Zeiss Oc. i and 1/18 oil immersion. Garnault says, 

 in speaking of formation of sperm nucleus in Ario7i and Helix, 

 " the spermatozoon enters just before first kinesis, or immediately 

 after. The contracted head does not begin to change until after 

 the expulsion of the second polar globule. The sperm-head first 

 divides into two chromatin spherules, then, by successive divisions, 

 there is formed a greater number of spherules which remain 

 inclosed in a clear areole. This clear areole recalls the hyaline 

 centre of attraction when that has received the half plate for the 

 formation of a vesicular nucleus." * 



* The following few notes pertaining to the fixing and staining oi freshly 

 laid eggs may be of interest : — 



Eggs placed for five minutes in Fol 99 (i per cent, chromic, 25 vol ; 2 per 

 cent, acetic, 50 vol ; H.^O, 25 vol), then shelled in water ; vitellus in same 

 solution for five minutes, H2O ten minutes., and 35 per cent, and 50 per cent, 

 alcohol five minutes each, 70 per cent, thirty minutes, and 90 per cent, ad lib., 

 gave good results, taking picrocarminate of lithium very well if left long enough 

 in stain. They also took borax carmine very well after the above treatment. 



Both of these stains did well after the eggs were immersed in chromic J per 

 cent, ten minutes, then shelled in large quantity of water, then vitellus in 

 chromic J per cent, four minutes, and H2O and grades of alcohol as above. 



Whole egg in osmic acid i per cent, five minutes, followed by Merkel's fluid 

 four hours ; shell, then water, and grades of alcohol two minutes each to 70 

 per cent, for permanent preservation were quite satisfactory. It gave good 

 results as to nuclei when eggs were left in picrocarminate of lithium for 

 forty-eight hours. 



The Torpedo Fish. — At the last meeting of the Academy of 

 Science, Philadelphia, Prof. D'Arsonval, of the College de France, 

 said : — A fish 30 cm. in diameter could give out a shock of 20 

 volts. He applied some small electric lamps to the fish, and they 

 were lit by the discharge from its body. In some instances they 

 were so powerful as to carbonise the lamps. — Sci. American. 



