THE ACARIJs^A OR MITES. 



117 



In Europe it has lately been proA ed that tliis or an allied species does great damage 

 to the roots of grapevines, and that it may l)e destroyed by the use of carl^on l)isulphid 

 injected into the soil above the infested roots. Another species has been found to 

 eat through the grafting wax on budded plants, bore beneath the bark, and so pre- 

 vent the union of graft and stock. A species described by Riley, R. phylloxeme, 

 was supposed to feed on the Phylloxera, but it doubtless fed 

 on the grape roots and is common on deca^dng roots and 

 tubers in the Eastern States. It may aid in the distribution 

 of disease. 



The typical species of Carpoglyphus, C. passularum Her- 

 ing (fig. 234), has been found on dried figs in California 

 and elsewhere, on dried apples, smoked ham, and on pollen 

 of honeybees. It infests dried fruit in Europe. In tliis 

 genus there is no furrow separating the cephalothorax and 

 abdomen. The position of the long hau* on the tibia of legs 

 I and II is different from that of any other tjToglypliid. 

 This hair is normally near the tip of the tibia, but in tliis 

 genus it arises from near the middle of the joint. There are 

 only short hairs on the dorsum of the body, but at the tip are two long hairs each 

 side. It is claimed that the female is ovoviviparous. 



One species of Histiogastei' (fig. 242) is known from Arizona, where it burrows 

 in the decajdng stems of alfalfa; a similar species in Europe burrows in the stems 

 of reeds It is not certain whether they attack healthy tissue, but from the near 



Fig. 2i0.— Mor.ieziella sp.: 

 Mandible and venter. 

 (Author's illustration.) 



■Histiogaster xylophagc 

 (Original.) 



Fig. 2A\.—Monieziclla sp., 

 from San Jose scale. (Orig- Fig. 242. 



inal.) 



relation of the genus to RMzoglyphus it is probable that they do so, and thus give 

 entrance to destructive fungi. The hypopus of Histiogaster has a glassy eyelike 

 spot on each anterior side of the body; there is no evidence that it is an organ of 

 vision. The species of the genus Trichotarsus (formerly Trichodactylus) are peculiar 

 in that they occur in hypopial form on bees. They have a l)road body, "s\'ithout 

 division into cephalothorax and abdomen, and provided with a few short hairs. 



