A SYNOPSIS OF AUSTKALIAN ACARINA — RAINBOW. 157 



out^" that these mites differ from Rhyncholophida; in that the hist 

 joint of leg iv. is not or very slightly shorter than the penultimate, 

 and also that the last joint of leg iv. is not swollen. In leg i. the 

 last joint is usually swollen, often more so than in species of the 

 family last quoted. They are also red in colour, though some 

 species are darker than others ; the body is clothed with bristles 

 or feathered hairs according to the species. The palpi are five- 

 jointed, prominent, often swollen at the middle, the penultimate 

 joint ending in one or two claws, the last joint appearing as an 

 appendage or " thumb " to the one preceding. Legs seven-jointed 

 and clothed similarly to the body ; tarsi terminating with two 

 small claws. The cephalothorax has a crista running down the 

 middle, and this is enlarged at the centre or posterior extremity 

 into a triangular space known as the areola in which are two pores 

 from which arise bristles. Two eyes are placed on each side of 

 the cephalothorax, and these are frequently elevated upon long 

 pedicels. 



In the larval form, these Acarids are parasitic, and are found 

 at times on lieetles, butterflies, moths, flies, mosquitoes. Mr. G. 

 A. Waterhouse, B.8c., has taken the Leptns (ov larval form) of a 

 Trombidium from butterflies collected by him on Mt. Kosciusko. 

 Mr. G. Goldfinch has also collected forms of Leptus from the 

 common house-fly. The mature Trombidiidte feed on insects — 

 plant lice, caterpillars and the like. In the United States one 

 species, Trombidium locusta7-um, Riley, destroys numbers of 

 grasshopper eggs, and in France a species has been recorded as 

 destroying the root forms of Phylloxera, that scourge of the vine. 



In Europe, Japan and America, the larval forms of Trombi- 

 diidse, when numei-ous, are sometimes known to attack man, 

 causing intense irritation and pain, and have even been known to 

 promote serious complications. In the United States they are 

 known, when found upon man as " Red Bug." These larval 

 mites burrow beneath the skin and produce inflamed spots. As 

 Banks jDoints out, " this is an unnatural position for the mites, 

 and they soon die, but the waiting is not pleasant. In France 

 these pests are known as rouget or aoittat, and are the cause of 

 Erythema autumnale ; in Germany they produce Stachelbeerkrnn- 

 theit. In England they are called " Harvest Mites " or " Goose- 

 berry Bugs " ; in Mexico, Tlalsahtiate ; Japan, Akamushi ; and 

 the West Indies, Bete-rouge. 



10 Biinks--Lor>. ci(., p. 30. 



