PAKASITES OF SPIDERS AND THEIR EGGS. 59 



Micaria (unknown). Pezomachu.s obscurus. Egg parasite. 



" " Heniitcles micarivora. " " 



Prasthesima furcata. Hemitelcs prosthesiniBe. " 



Drassid (unknown). Hemitelcs ilrassi. " 



Drassus lapidicolens. Polyspliinct^i tuberosa.* F>ody parasite. 



Agrujca brunnea. Hemiteles tenerrimus.* Egg parasite. 



" " Hemitelcs aranearuni.* " " 



" " Hemitelcs forniosus.* Body jjarasite. 



" " Pezomaehus fasciatus.* Egg parasite. 



" " Pezomachus corrupter.* " " 



" " Pezomachus proximua. " " 



" " Pezomachus zonatus.* " " 



Drassid (unknown). Eupclmus drassi. " " 



Laterigrade, Saltigrade, Citigrade. 



Laterigrade cocoon. Pezomachus gracile. EL'g parasit<^. 



Icius (unknown). Polysphincta n. sp. Body parasite. 



SaVtis pulex. Acoloidcs saitides. Egg parasite. 



Phidippus morsitans. '" " " " 



Pardosa luteola. Polysphincta . Body parasite. 



IX. 



It is difficult to make any correct genei'alizations from the data in hand 



on this most interesting chapter in the biology of spiders, since the species 



or even genus of the host is in so many cases unknown, even 



.. when the parasite lias been determined. But a few hints appear 



zations. '^ . . ^ ^ . 



from the study of the above lists and preceding facts which 

 may serve to at least open the way for others who in the future may 

 have more perfect information. 



First, it is evident that the exchmve occupation of a S2>cc>Jic host by a 

 specific ()iwst is not the fixed ride. For example, the eggs of Argiope co- 

 phinaria are jiarasitized by one species of Pezomachus, two of Pimpla, and 

 two (though perhaps as hyperparasitcs) of Chrysocharis. Again, Epeira 

 diademata of Europe serves as body host for three species of Polysphincta, 

 and its eggs as host of one each of Ilemiteles and Pimpla. Once more, 

 Agroeca brunnea of Europe has one species of Hemitelcs for a body para- 

 site (?), and for egg parasites two species of Hemitelcs and throe of 

 Pezomachus. Thus it would appear that the occupation of any specified 

 host is not limited to any specilic guest, but has a wide possible range, 

 both as to species and genera. 



Second, the preference of any specific giwst is not aliuays confined to one 

 specific hont. Thus, Polysphincta carbonator, a European body parasite, is 

 rejiorted as guest upon three species of Epeira ; and Polysjihincta booi)s 

 uj)on both Theridion and Epeira. 



Third, the guests are not absolutely separated by their habits into dislincl 

 groups of body parasites, on the one hand, and nest parasites on the other. 

 Thus, Polysphincta carbonator is a body parasite upon three Epeiroid 

 species, but is reported as a guest upon unknown spider eggs; P. rulipes 



