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creep slyly away. The others of the young would not act in this way, how- 

 ever much they were teased. It would be interesting to know whether all 

 the adults possess this odd habit, or only a portion of them. 



The cuticle of the young Helerodnns is shed very shortly after their escape 

 from the egg- coverings. Within a few minutes after one had left its prison 

 the skin was observed to be broken about the head. It had left the egg at 

 half-past ] and by 4 o'clock the skin was pushed back half the length of 

 the body. The next morning the skin was wholly slied, revealing the 

 brighter colors of the new skin. While getting rid of the cuticle the little 

 reptile kept crawling over the clay and among the roots of grass. 



The opportunity was embraced to observe the use which is made of the 

 egg-tooth. The tooth itself is easily seen in the just-hatched snake. Its 

 lateral borders are more nearly parallel than those of the tooth of Bascanion 

 figured by Weinland. Seen from the side, the anterior or upper outline is 

 concave, the posterior outline convex. Thus, the tooth projects forward 

 and is turned slightly up. The anterior face is also concave from side to 

 side, so that there is, on each side, a distinct cutting edge. The tip is cut 

 off square. The tooth appears to have a ligamentous attachment, and may 

 be lifted a little, but not much depressed. It seems quite evident that the 

 tooth is first engaged in the egg-covering and then made to do its work by 

 a forward push of the head. An examination of the covering, after the 

 snake has left it, gives ample proof that it has been cut and not merely 

 torn. The edges are as smooth as if they had been slashed with a razor. 

 A long slit is sometimes made as if by a single effort. In other cases, sev- 

 eral attempts appear to have been made before the covering has been open 

 enough for the snake to get out. In one or two cases, a tooth has not been 

 inserted deeply enough, and the only result was a scratch on the inside of 

 the covering. The egg tooth having performed its office becomes loose and 

 drops out. This occurs usually within twenty-four hours. 



When the slit has been successfully made, the little snake may sometimes 

 be seen pushing its head carefully out as if to survey the surroundings. 

 Should there be any movement, the head will be quickly withdrawn! 



I have been able to collect some facts concerning the pairing of the sexes 

 of Heterodon platirhinos. Prof. U. O. Cox, of Mankato, Minn., informs me 

 that he found two individuals uniting some time in May. A second male 

 was entwined with the two other snakes. The latter were separated with 

 difficulty. The male intromittent organs are described as being of an oval 

 form, an inch long and over a half inch thick. 



