76 



PROCEEDINGS OF THE -NATIONAL MUSEUM. 



VOL. XXVIII. 



The ])0(]y of the male ends in a broad sucker, wherein is situated the 

 penis. The tip of the female is g-rasped by this sucker. P. ventri- 

 cosus occurs connnonly in this country, and another species has been 



found on the . larvae of scol3^tid 

 l)eetles. Professor Herrera, the 

 Mexican entomologist, has en- 

 deavored to breed, a Mexican 

 species to kill the g-rubs of the 

 cotton-})oll weevil. 



Se\eral other species hav^e been 

 assigned to this genus which feed 

 on gi'ain and grasses. One would 

 suspect that the}' would fall in a 

 separate genus, for which the name 

 Siterojjtes Amerling is available. 

 One is P. tritJci^ found in wheat 

 heads; another is P. grariiinis 

 which Renter has described as 

 partly responsible for '"silver-top'" 

 in certain grasses. 



Pi(jinc<>j>Jnn'"K is closely allied to 

 Pf'dicubiidex. It has a migratorial 

 form, which in one case was found 

 A\'e have 



Fig. 147. — Tarsonemus pallidus. 



on a mole, and in another on a tiy 

 observed a species in this countr}' attached in 

 some numbers to a fly — Platycnemh tmix i-- 

 ftrta. The genus 

 Podapollpus has been 

 found upon grasshop- 

 pers. The male is re- 

 ported to have but 

 three pairs of legs, and 

 the female but two 

 pairs. 



In the Tarxonemaia^ 

 are two genera — Tar- 

 xoiieiiiiis: and Dlspari- 

 pfS. The species of 



TarsoiU'inus affect various plants, sometimes 

 producing galls upon them. They live in col- 

 onies upon the leaf or stem, or in the culms 

 of grasses. One s[)ecies, T. on/ZcV, infests rice in Italy: another, T. 

 cnliiilcola, produces ** silver-top '' in certain grasses of Finland; a 

 similar form produces the .same appearance in some grasses of New 

 Mexico. One grass-stem may contain several million mites. Another 

 s|)ecies does consideral*!!^ damage to tc;i in C'cyloii. Tryon has 



-TAKSdXKMrS I. ATI'S, 

 KIC.MALE. 



-T.\HSl)XE.MU.S I.ATU.- 

 MAI.E. 



