106 ENTOMOLOGICAL SOCIETY 



there are spines on the anterior coxae, as in E. solitaria, E. 

 angulata, and E. silvatica. These species also have the tibia 

 and metatarus of leg II modified as above. Similar projections 

 on the coxae will be noticed in some Clubionidae. In those 

 Epeirids that have humps or spines on the abdomen the male sex 

 is almost destitute of such characters. The head of male Epeirids 

 is nearly always narrower than that of the female. 



In the Theridiidae there are a large number of differences in 

 the sexes. In Microdipoena there is a curved, spine-like pro 

 jection at the tips of the anterior tibiae and metatarsi. A similar 

 structure is found in some tarantulas. The head of the male of 

 this genus is much higher than in the female ; this is a very com 

 mon difference in the family. In Theridium frondeum and one 

 or two allied species there is a small hump at the base of the 

 mandibles in the male. The mandibles are elongate and toothed 

 in the male of Theridium sexpunctatum\ and in certain species 

 of Linyphia and Erigone. In the males of some species of 

 Tmeticus and Microneta there is a spine on the front of each 

 mandible. In T. tridcntata there is a row of teeth on the sides 

 of the mandibles, and in the female these are present in a rudi 

 mentary condition. In some species of Erigone the sides of the 

 thorax in the male are spiny. In a number of micro-therididac 

 {^Lophocarenum , some Ceratinella, etc.) the head of the male is 

 curiously modified ; elevated into humps of various shapes, and 

 in the former genus with a little hole on each side. In the male 

 of Tmeticus unicornis there is a prominent projection on the 

 clypeus ; a similar one exists in the male of Histiagonia rostrata. 

 In the latter and in the allied Ancylorrhanis hirsuta there is a 

 corneus shield on the abdomen of the male. In Ceratinella the 

 males possess a similar shield above and sometimes also below ; 

 in some species it may be present in the female. In Cornicularia 

 there is a horn between the eyes of the male. In Erigonoplus 

 the male has the metatarsus of the front legs greatly swollen ; 

 this genus has the head lobed as in Lophocarenum. In the male 

 of Maso the head is much broader than in the female. 



The importance of the sexual peculiarities of the micro- 

 therididae is not understood. Though they are not ornamental 

 in our eyes, they serve to give a distinctness to the male which 

 may be of service in enabling the female to recognize her proper 

 male ; for except in these secondary sexual characters and in the 

 genitalia (accessory) the species are much alike. In Asagena 

 the cephalothorax is rougher in the male than in the female, and 

 it is said that these spiders make a noise by rubbing the base of 

 the abdomen over the cephalothorax, but it has not been observed 

 in the American species. In this genus the second pair of legs 

 is very spiny in the male. 



In the Agalenidae two species of Hahnia have the hairs on the 



