1902.] Properties of Saliva of '" Non-poisonous " Colubrines. 451 



Post mortem. — There was very marked extravasation over the back 

 at and beyond the site of injection. 



Experiment 6. — As a control experiment, a small black-and-white 

 mouse was injected under the skin of the back with 4 minims of 

 fresh serum of the same Dryophis whose glands were used in Ex- 

 periment 5. The animal was closely watched for 70 minutes, but 

 no symptoms of poisoning appeared, and it was quite well several 

 days afterwards. 



Remarks on Experiments 1, 2, 4, and 5. 



No one who has experimented with minimal lethal doses of Cobra 

 venom can fail to be struck with the close resemblance of the symp- 

 toms caused by it with those recorded in the above experiments with 

 the parotid secretion of Dryophis and its Opisthoglyphous allies. 



The gradual quickening of the respiration, the drowsiness and 

 nodding of the head, with jerky recovery every now and then, fol- 

 lowed by gradually increasing paralysis, and a rapid failure of the 

 respirations after they have become laboured in character, by convul- 

 sions, and finally by stoppage of the heart some little time after the 

 breathing has ceased, form a sequence of events that, except for a 

 difference in intensity, are common to both, as also is the post-mortem 

 picture of subcutaneous extravasation. 



B. Experiments with Aglyphous Colubrines. 

 iv. Zamenis mucosus. 



Experiment 7. — A black-and-white mouse was injected under the 

 skin of the back with half the extract in distilled water of one parotid 

 gland of a large snake. The extract, instead of being a thin opales- 

 cent fluid as in the Opisthoglyphous snakes, resembled ropy mucus. 

 Eight minutes afterwards the animal appeared to be quite well, but in 

 21 minutes from the time of injection it died in violent convulsions. 



Experiment 8. — A mouse was injected under the skin of the back 

 with 1 c.c. of the watery extract of one parotid gland of a Zamenis 

 mucosus nearly 7 J feet long. Five minutes afterwards it looked 

 anxious and depressed. At 7 minutes the respirations were twenty- 

 nine in 15 seconds. At 9 minutes the hind legs were dragging 

 slightly. At 10 minutes the respirations were twenty-eight in 

 15 seconds, and the animal could walk fairly well. At 14 minutes 

 the respirations were nineteen in 15 seconds and very laboured : the 

 animal could still walk. At 17 minutes the respirations were ten in 

 15 seconds, laboured and gasping. At 18 minutes the animal was 

 extremely restless. At 20 minutes violent convulsions and leaping 

 occurred, which ended in the animal rolling over on its side, the 



