The SOLPUGIDA are peculiar spider-like forms which are distinguished from nearly all other arachnids by the fact that they possess no true cephalothorax, the last two leg-bearing segments being distinct, resembling those of the abdomen in this respect. The first pair of legs is not used in locomotion but seemingly functions as a second pair of pedipalpi. Figure 12 illustrates the striking peculiarities of the group. They are primarily desert forms and occur in the warm zones of all countries. Of the two hundred or more species, Comstock lists twelve as occurring in our fauna. These occur primarily in the southwest. [Illustration: 12. A solpugid (Eremobates cinerea). After Comstock.] The Solpugida have long borne a bad reputation and, regarding virulence, have been classed with the scorpions. Among the effects of their bites have been described painful swelling, gangrene, loss of speech, cramps, delirium, unconsciousness and even death. Opposed to the numerous loose accounts of poisoning, there are a number of careful records by physicians and zoölogists which indicate clearly that the effects are local and though they may be severe, they show not the slightest symptom of direct poisoning. More important in the consideration of the question is the fact that there are neither poison glands nor pores in the fangs for the exit of any poisonous secretion. This is the testimony of a number of prominent zoölogists, among whom is Dr. A. Walter, who wrote to Kobert at length on the subject and whose conclusions are presented by him. However, it should be noted that the fangs are very powerful and are used in such a manner that they may inflict especially severe wounds. Thus, there may be more opportunity for secondary infection than is usual in the case of insect wounds. The treatment of the bite of the Solpugida is, therefore, a matter of preventing infection. The wound should be allowed to bleed freely and then washed out with a 1:3000 solution of corrosive sublimate, and, if severe, a wet dressing of this should be applied. If infection takes place, it should be treated in the usual manner, regardless of its origin. THE ACARINA, OR MITES AND TICKS A number of the parasitic Acarina evidently secrete a specific poison, presumably carried by the saliva, but in most cases its effect on man is insignificant. There is an abundant literature dealing with the poisonous effect of the bite of these forms, especially the ticks, but until recently it has been confused by failure to recognize that various species may transmit diseases of man, rather than produce injury through direct poisoning. We shall therefore discuss the Acarina more especially in subsequent chapters, dealing with parasitism and with disease transmission.