Four nyrnphal instars are invariable in our numerous observa- 

 tions. Nymphs, like adults, feed for from 25 to fifty minutes. 

 The first nyrnphal instar, however, never feeds ; it raolts to the 

 second instar usually in ten to thirteen days (rajige eight to 21 

 days). One to three weeks later the second instar nymph feeds 

 and molts to the third instar some two weeks later (range eight 

 to 23 days). The third instar nymph takes food between three and 

 35 days afterwards and molts three or four weeks later (range 

 fifteen to 59 days). The fourth instar nymph feeds between five 

 and 36 days afterwards and molts to the adult stage three or four 

 weeks later (range seventeen to forty days). 



Note that although there are many nfflrphological similarities 

 between A, confusus and A, boueti , the biology of the nyrnphal stage 

 of each is distinct. 



In this species, the observed period between nymphal molting 

 and feeding is quite variable. Some accept food within five to 

 seven days although two to three weeks, or longer, is more common 

 for this and for other bat- parasitizing argasids. Also noteworthy 

 is (1 ) the average two week postf eeding period of second instar 

 nymphs in contrast to the three or foior week average postf eeding 

 period of the tv;o subsequent instars, ajnd (2) the nonf eeding first 

 instar. 



Adults placed together shortly after molting have been observed 

 to mate only after feeding which may occur from eight to sixteen 

 days after molting. The feeding period varies from forty minutes 

 to two hours. No egg batches have been deposited before three and 

 a half to four months after molting. Further studies on the F^ 

 generation are in progress, 



Fcology 



We have collected, with considerable and strenuous effort, 

 several hundred specimens of A. confxisus in Egypt. This species, 

 together with A. transgariepinus , is the most secretive of bat in- 

 festing argasi"3s. It wedges itself deeply into the narrowest 

 crevices of caves and of hillside crannies in which bats rest. 

 It is never found easily or in groups of more than two to a max- 

 imum of twelve specimens. We know of only a single exceedingly 

 small population in Cairo, where bats roost in buildings that 

 are more humid than desert caves. In the environs of Cairo, A. 



_ 100 _ 



