INSECT POISONING AND MISCELLANEOUS NOTES 465 



of venom claws which are large-clawed appendages lying beneath the 

 head. The opening of the venom duct in Ethmostigmus spinosus, which 

 has been carefully studied by Cornwall, is on the dorsal surface of the 

 claw a little way from the apex and somewhat near the external side. 

 There is one venom gland in each of two venom claws. This species is 

 nocturnal in habit and is not naturally vicious and will not bite unless 

 hurt or worried. A centipede's bite may be merely a snap, but once he finds 

 his fangs sink into the fine tissues his main idea, if other portions of him 

 are not being mistreated, seems to be to eat. To this end he digs as many 

 legs as he can apply into the subject, the posterior ones to obtain a firm 

 hold, and the anterior ones to knead the tissues. The venom claws are 

 worked in and out and with the help of the first pair of legs the skin of 

 the subject is pushed into the mouth. In five minutes a centipede will 

 thus consume a length of rabbit skin nearly one centimeter long. The 

 main function of the venom claws is to hold the food tightly against the 

 mouth-parts to facilitate mastication. The slow but regularly continued 



Fio. 88. — A centipede, Scolopendra morsitans (Bradford). 



relaxation and closing of the venom claws is designed to permit the flow 

 of venom into that part of the food which is to be taken into the 

 mouth. The toxic action is so slow that the venom would be practically 

 useless for destruction or defense. Cornwall believes therefore that the 

 venom principally serves as a digestive juice. 



Other species of centipedes which have been recorded as venomous are 

 Scolopendra cmgulata Latreille, S. gigantea Linnaeus, iS. morsitans Lin- 

 naeus (fig. 88), S. heros Girard, and Geophilus similis Leach. 



The centipede bite may cause some local pain, swelling, and erythema 

 lasting a few hours. The general symptoms are great mental anxiety, 

 vomiting, irregular pulse, dizziness, and headache. When severe local 

 inflammation follows a centipede bite, it is chiefly due to septic infection. 

 A large centipede which has secured a firm hold of the skin by digging in 

 its fangs and legs can almost be torn in half before it can be induced to let 

 go, and in delicate skins each leg can, under such circumstances, make a 

 punctured wound which will admit infective organisms. The use of dis- 

 infectants to prevent infection by outside organisms is therefore neces- 

 sary, 



Vorhies has described two cases of Arizona centipede bite, in both 

 of which the pain was severe and prevented sleep. 



