54 NATURE STUDIES. 



upon the virulence of the poison, Helodcrma was made 

 to bite a frog and a guinea-pig. The frog died in one 

 minute, and the guinea-pig in three. The virus re- 

 quired to produce these effects must be of singularly 

 acute and powerful nature. It is to be hoped that no 

 case of human misadventure at the teeth of Helodcrma 

 may happen. There can be no question, judging from 

 the analogy of serpent-bite, that the poison of the 

 lizard would affect man. The sacrifice of a guinea-pig 

 and a frog may be, and most probably will be, cited 

 by rabid anti-vivisectionists as a cruel experiment. 

 Sensible persons will apply another term to the test 

 whereby the virulence of the lizard was established, and 

 humanity thereby placed on its guard. Forewarned 

 is forearmed, whether we consider the case of a 

 burglarious attack on our premises or the bite of a 

 lizard. 



BIRDS WITH TEETH. 



BY THOS. FOSTER. 



IN the year 1861 a feather was found in a slab of 

 lithographic stone from Solenhofen, which Hermann 

 von Meyer assigned to an animal as yet not otherwise 

 known, which he called Archceoptcryx lithographica. 

 Later in the same year, a large portion of the skeleton 

 of Archseopteryx was discovered in the same forma- 

 tion. There were impressions of feathers radiating 



