HABITS AND LIFE HISTORY OF THE TOADFISH. 1 097 



During the summers of 1906 and 1907 hot a single ripe female was captured, 

 and but two with ovaries anywhere near maturity. One of these ovaries is 

 shown in figure 2, plate cvii. The other was in about the same stage. On June 

 22, 1908, Prof. Raymond Binford, of Guilford College, N. C, in searching for 

 Ascaris, killed a 6|<{'-inch toad which on dissection proved to be a female with 

 ripe ovaries containing about 40 eggs. The ovaries were opened and the eggs 

 were run into fresh salt water. A ripe male being at hand it was quickly opened 

 and the testis was minced up and parts put into the same dish with the eggs. 

 After about ten minutes the water with the minced-up testis was poured off 

 and the eggs covered with fresh clean water. 



Fertilization was effected about 12 noon. The eggs at 6 p. m. were in the 

 4-celled stage. Segmentation must have begun about 5, possibly as early as 4.30. 

 At Woods Hole, Miss Clapp (1891 and 1899a) found that segmentation began 

 seven hours after fertilization (artificial) was effected. In the above experi- 

 ment, segmentation began within four and one-half or five hours after the eggs 

 were impregnated. The explanation is undoubtedly to be found in the great 

 difference in the temperature of the water. Miss Clapp does not give the tem- 

 perature for her experiments , but at 3 . 1 5 p . m . on the day referred to a thermometer 

 hung in running sea water in the Beaufort laboratory registered 81° F. In 

 this difference in temperature of the harbor water at Woods Hole and Beaufort 

 is also to be found the explanation of the ease with which Miss Clapp could get 

 ripe females and of the difficulty I experienced in getting even one. 



Owing to the low temperature at Woods Hole the breeding season for the 

 toadfish is restricted to a comparatively short time. Dr. Raymond C. Osburn, 

 of Columbia University, at my request, has carefully gone over the Woods Hole 

 records. He writes me that they show that spawning goes on during the month 

 of June only (except of course in some few sporadic cases), beginning sometimes 

 as early as the first week in June. He writes that the most extensive and 

 authentic records have been made by Mr. J. T. Patterson, who notes that in 

 1906 the spawning period extended from June 12 to June 25. Speaking for 

 himself, Doctor Osburn says: 



It is my own experience that the eggs are mostly hatched by the first week in July; 

 that is, they have broken the egg membranes. I know this because I have often looked 

 for them here after coming the first of July, and I have never yet succeeded in finding 

 eggs that were entirely fresh at that time. 



In a letter to the present writer, dated July 24, 1906, Vinal N. Edwards, 

 the veteran collector of the Fisheries Laboratory at Woods Hole, says that he 

 does not find any toadfish with eggs after the first of July. He adds, however, 

 that in the fall, when he sets his fyke nets, he catches large numbers of large 

 fish full of spawn, but they carry it all winter. 



B. B. F. 1908 — Pt 2—27 



