202 Strecker — Notes on Life History of Scaphiopus couchii Baird. 



Breeding Habits. — The clasp of the male is inguinal as is 

 usual in the family ( Pelobatidae) . About three hours is usually 

 required for the laying of the complement of from 350 to 500 

 eggs, and during this time there are from four to eight periods 

 of sexual activity. A captive pair remained in copula for 

 nearly eight hours but this is unusual. 



The eggs are in strings, in double and even triple rows. 

 These strings range from 1^ to 21 inches in length, and the 

 number of eggs in a string varies from 45 to 125. The pig- 

 mented portion of the egg is black and the yolk porcelain white, 

 while the surrounding jelly mass is almost colorless. The 

 diameter is about one-sixteenth of an inch. The largest num- 

 ber deposited by one female was 528; the smallest, 343. 



The eggs are attached to grass, weeds and rootlets, in from 

 3 to G inches of water. They are very bouyant and readily 

 float on the surface. I made a careful count of the number of 

 eggs in the eleven strings comprised in two full complements, 

 and the result is as follows: 



The eggs hatch in from eight to 'ten days. The newly 

 hatched larvae are tender and rather inactive, but their growth 

 is exceedingly rapid, and within the course of a very few days 

 they are swimming freely in the shallower portions of the pond. 

 In form the week-old tadpole is short and plump. The gen- 

 eral color is blackish-brown, lighter on the belly and tail. The 

 latter, which is unusually slender, is sometimes more or less 

 blotched and spotted with darker shades. 



On the 12th or 13th day after hatching the limbs begin to 

 appear, and from this time until they are ready to leave the 

 water the tadpoles are usually found in shallow water close in 

 to the edge of the bank. A dip-net will bring up scores of them 

 in one sweep. On the 19th or 20th day the little animals leave 

 the water with their tails still in evidence. They are now 

 about 14 or 15 mm. in length, and the short tail is probably 

 absorbed within the next three or four days. It is a difficult 

 matter to be certain of this, however, as they commence to 

 burrow within a few hours after leaving the water. 



