392 



NOTES ON THE BKEEDING HABITS 



of the stomach to the proximal end of the rectum. Their lengths 

 are recorded in the accompanying table for the wood-frog : — 



a 



d 



e 



f 



g 



(a) From a large tadpole with whole tail and two large posterior feet. 



((^) From a tadpole with whole tail and two large posterior feet. 



{c) From a tadpole with whole tail and two large posterior feet. 



(d) From a young frog, tail beginning to disappear, and four feet. 



{e) P'rom a young frog, 4/5 tail, and four feet. 



(/) From a young frog, 1/2 tail, and four feet. 



(g) From a young frog, no tail, and out of water two weeks. 



IX. — Methods of Technique.— The eggs during the periods 



in which it is difficult or impossible to remove the inner jelly 

 membrane, can be freed in the following manner : — With a pair of 



sharp scissors each egg must be cut out from the general jelly mass, 



retaining as small an aixiount of surrounding jelly as possible. It 



is then put into an alcoholic solution of picric acid for an hour or 



longer (one to twelve). The solution is prepared by saturating 



35 per cent, alcohol with picric acid, and adding the same amount 



of sulphuric as in Kleinenberg's solution. The solution is not 



diluted, but used saturated with picric acid. The eggs are then 



washed for several hours in 35 per cent, alcohol, several hours in 



50 per cent, alcohol, and placed in 70 per cent, for several days, 



changing the alcohol once or twice if necessary. About the second 



