How Many Times does the Snapping Turtle 

 lay Eggs in One Season P 



By 



K. Mitsukuri. 



(Preliminary Communication.) 



There is in Fukagawa, a suburb of Tokyo a large turtle-farm where 

 a large number of our Snapping-Turtle {Trionyx Japonicus, Schlegel ; 

 Jap. Suppon) is annually bred for the market. For several consecutive 

 years, Mr. Hattori, the proprietor kept at my request the records of 

 egg-laying at his farm. Each deposit of eggs was numbered, and the 

 following particulars were noted in regard to it : (1) the date of deposi- 

 tion, (2) the date of hatching out, (8) the number of eggs in the deposit 

 and (4) the number of eggs that hatched out. By constructing graphic 

 tables of various kinds from the data collected in these records, I tried 

 to bring out some facts in regard to the breeding habits of the Suppon. 

 Among other things, I tried to make out how many deposits one in- 

 dividual makes in the course of one season. The graphic diagrams were 

 not, however, conclusive in the point, although it was evident that more 

 than one deposit was made. The probabilities were that the number 

 differed with individuals or even in the same individuals with dilferent 

 seasons. 



Eeceiitly Mr. Hattori made some observations which seem to throw 

 a great deal of light on the point in question and to which I wish to call 

 attention. In 1894, Mr. Hattori kept a pair of large Suppons by 

 themselves in a separate pond. The male weighed 1724 grammes and 

 the female 2662 grammes. Altogether /o?/j- deposits of eggs were made 

 in the course of the breeding season of that year. The records may be 

 tabulated as follows : — 



