NOTES FROM THE ZOOLOGICAL GARDENS. 589 



kinds and the easy escape of the swifter snakes, will admit 

 the importance of providing them with such retreat and 

 shelter as can be most speedily arranged, and which will 

 secure the least annoyance to the terrified serpents while 

 the keepers are doing their best to preserve order and 

 cleanliness. 



The allusion to lizards tempts me to add a word or two 

 on the exceptional species which has lately become 

 an inmate of our Zoological Gardens. There are certain 

 features in it so much in common with viperine snakes, that 

 I may be pardoned for dragging a lizard into these pages. 

 I allude to the Heloderm {Helodcnna Jiorriduni) from 

 Mexico, presented to the Zoological Society in July 

 1882 by Sir John Lubbock. Its advent was an event 

 in reptilian annals ; and being surrounded by a halo 

 of curiosity, it claims a passing notice. We have been at 

 some pains to exonerate saurians from the evil character 

 which our ancestors were apt to give them ; but suddenly 

 — and to the surprise of even some herpetological autho- 

 rities — there comes a lizard that with one grip of his jaws 

 caused a frog to fall dead in a moment, and a guinea- 

 pig in three minutes, the symptoms appearing to be the 

 same as those produced by deadly snakes. The Heloderm 

 is ' said ' to be furnished with poison glands in both jaws ! 

 But until a dead specimen has been further examined and 

 described, the signification of ' poison gland ' must be 

 restricted. Its teeth— many and strong — are grooved with 

 a deep furrow ; its salivary glands are largely developed ; and 

 under excitement a thick, acrid secretion flows abundantly 

 from its jaws. Yet so far as present observations enable us 



