SCIENCE-GOSSIP. 



219 



Fie;. 71.— Expanding bud of Spanish chestnut in which 

 bud-scales = stipules of leaves; s, bud-scale. 



the gradual passage of the bud-scales into stipules 

 is readily seen. The leaves to which these stipules 

 belong are, for the most part, normally developed. 



IV. — Bud-Scale— Stipules of Arrested Leaves. 

 In some cases, as in oak and beech, we find only 

 the stipules of the lowest leaves becoming evident, 

 whilst it requires careful microscopic examination 

 to show an indication of blade and base. These 

 stipules, moreover, have lost their usual appearance 

 and become membranous in texture. 



Fig. 76. — Shoot of Spanish chestnut in which stipules of 

 leaf = bud-scales. 



We thus see how each portion of the leaf 

 may become modified in order to enable it to 

 serve as a protection to the parts of the shoot 

 which are younger, and we learn from such con- 

 siderations as these how plastic are the members 

 of the plant body, and how readily they respond to 

 external influences. 

 Elmwood, Bickky, Kent; June $th, 1894. 



THE BITE OF THE GILA MONSTER. 

 By C. A. Mitchell B.A. (Oxox). 



XHE Gila Monster, or Heloderma suspectum, has 

 long had the reputation of being the only 

 example of a poisonous lizard, and though it is 

 very doubtful whether it has ever destroyed human 

 life, it is held in very bad odour by the natives 

 in the districts where it occurs. Its home is in 

 North America, and it is found especially in New 

 Mexico, Arizona, and Texas. It is the largest 

 American lizard, and with its jet-black and orange 

 scales stands out as a striking object against a 

 dark background of rocks. In captivity it will feed 

 on rats, though its favourite food appears to be 

 hens' eggs. It is difficult to see of what use venom 

 can be to a reptile, the bite cf which is in itself 

 quite sufficient to kill the small creatures it feeds 

 upon. 



It has been the lot of the Heloderma to have had 

 its anatomy more thoroughly studied than that of 

 any other lizard, and every part of it has been 

 subjected to repeated and thorough examination 

 by various observers. To Professor Stewart is due 

 the credit of having settled the question of the 

 structures which had long been considered as the 

 ducts from the poisoned glands leading to openings 

 at the root of the teeth. He showed that in reality 

 these were branches of the inferior dental nerve 

 and blood vessels, and that the ducts from the 



supposed poison-glands led into openings under 

 the mucous membrane between the lip and the 

 jaw, so that there was no direct communication 

 with the teeth, as is the case with venomous 

 serpents. It w-ould thus appear that the saliva 

 must become impregnated with the poisonous 

 principle, and that when the animal bites, some 

 of this must run down into the wound. The fact 

 of the teeth being grooved and quite different 

 to those of ordinary lizards also leads to this 

 conclusion. 



As to whether the reptile really is venomous 

 there has been much discussion. Some have 

 affirmed that the poison is as active as that of a 

 viper, others that the saliva is absolutely without 

 effect on the animal system. Balancing the con- 

 flicting evidence, there appears to be little doubt 

 that the secreted fluid may, on certain occasions, 

 be rapidly fatal to small animals. Sir John 

 Lubbock stated that a specimen of the lizard, 

 which had been sent to this country, killed a frog 

 in a very short time, and a guinea-pig in three 

 minutes. 



In a paper published in the "Comptes Rendus," 

 for 1S75, F. Sumichrast wrote that he had arrived 

 at the conclusion that the popular belief as to its 

 venomous nature was not without foundation. A 



