300 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Birds of Illinois and Wisconsin.* — Charles B. Cory has published 

 an illustrated key to the 398 known birds of Illinois and Wisconsin, with 

 descriptions of their various plumages, nests and eggs, and geographical 

 distribution. 



Reptiles of Mexiana.f — G-. Haginann gives an interesting account 

 of the reptiles of this alluvial island in the Amazon estuary, which stands 

 only a few feet out of the water, and is completely flooded every March. 

 He discusses, among others, the beautiful tree-snake Trypanurgos com- 

 pressus, the anaconda Eunectes murinus, the large turtle Podocnemis 

 expansa, the caimans Caiman schrops and G. niger. There are many 

 interesting details given with regard to habits, e.g. the diet of snails in 

 the case of Dipsas bucephala and other Amblyeephalidge, as also of 

 Dracsena guianensis, which Goeldi regarded as a fish-eater. There is an 

 extraordinary photograph showing the abundance of caimans in their 

 " summer residence." 



Habits of American Toad.J — Newton Miller gives the following 

 summarv of his study of Bufo lentiginosus americanus Leconte. 



Bufo lentiginosus americanus spawns from the latter part of April to 

 the first of July. This species lays in small ponds, and only a portion 

 of each is used as a spawning ground. The males are the first to reach 

 the water in the spring ; 88 ■ 8 p.c. of all the toads in a pond at any 

 given time are males ; males are in proportion to females as SO " 7 : 100. 

 Trilling in full vigorous voice is heard only during the mating season. 

 Females respond to the call of the males. Males will not hold other 

 males. Spawn may be deposited at a depth of 18 in. or more. This 

 depth does not materially affect the hatching. Fertilisation takes place 

 in an improvised basket formed by the hind feet of the male and the 

 body and hind legs of the female. About 85 p.c. of the eggs laid in natural 

 ponds are fertile. Oviposition requires G to 18 hours. The laying of 

 two or four strands of eggs at a time cannot be considered of specific 

 importance. Toads lay 3,900 to 15,800 eggs at one laying. The eggs 

 hatch in 2 to 6 days, depending upon the temperature. Metamorphosis 

 takes place in 32 to 200 days. On an average, the tadpoles double their 

 weight seven times in 32 days. The tadpoles are omnivorous. Toads 

 feed entirely on animal matter ; no food is taken unless it shows signs 

 of life. Toads refuse no insects, worms, or slugs which they can swallow. 

 On an average, toads feed only once in a day and a half. The average 

 amount eaten in a day by a toad is 1'12 grin. About 80 p.c. of the 

 toad's food consists of harmful insects. Toads may be active from the 

 latter part of March to the middle of November. Toads are chiefly noc- 

 turnal. Toads go into the ground to pass the winter. The greater per- 

 centage of those that do not get below the frost-line perish. In the 

 strictest sense of the term, toads do not hibernate if kept in a warm 

 place. Toads feed throughout the winter if kept warm, although eating 

 comparatively little. No preparation is made for the winter other than 

 burying to a depth below the frost-line. Some toads do not hibernate 



* Field Mus. Nat. Hist. Chicago, ix. (1909) Publication 131, 764 pp. (many 

 figs.). t Zool. Jahrb., xxviii. (1909) pp. 473-504 (1 pi.). 



' t Amer. Nat., xliii. (1909) pp. 730-45. 



