Natural Enemies. 



115 



render effective service to man in destroying the locust. For 

 practical purposes, these may be divided into those which 

 attack the eggs and those which attack the active locust. 



ANIMALS THAT ATTACK THE EGGS. 



The Silky Mite (Trombidium sericeum, Say, Fig. 20.) — 

 This is a small scarlet animal about two lines long, which 

 has for some time been known to attack [Fig. 20.] 

 the eggs, and has particularly done good 

 service in the more Northern States. In 

 parts of Minnesota it has in many places 

 reduced the eggs to a powder, and the |''';^ ] '\\\^ ^ 

 ground has been alive with the little red, 

 active bodies. 



The accompanying figure represents 

 one about half grown. 



mi . , , m Silky Mite:— Natural 



lnis mite belongs to the genus Irom- size at side. 

 bidium, only two N. A. species of which have been described 

 viz., the scabrum, Say, and the sericeum, Say. The descrip- 

 tions in both instances are very brief, and it is difficult to 

 say whether the species in question belongs to either, as 

 it varies considerably with age. It answers to sericeum, 

 however, so far as the description goes, and I prefer to 

 so refer it rather than describe it as new. The specimens 

 which I have examined have not been full grown, and the 

 pale red color which they possessed would doubtless have 

 intensified with age. Every European is familiar with the 

 Scarlet Mite (T. holosericeum, X), which is common in the 

 soil of gardens in spring, and preys upon young larvae of 

 various descriptions. In color, silkiness and habit it greatly 

 resembles our species, and may indeed be identical. All the 

 species of this genus are highly colored, and the Trom- 

 bidium tinctorium found in Guinea and Surinam is em- 

 ployed as a dye. 



