71 



mite which devotes special attention to them ; another species is found only on various 

 members of the family of Cacti ; while there are still other species which affect other 

 plants, shrubs and trees. Since the habits of all these are similar the remedies recommend- 

 ed for the red spider, will probably prove equally efficacious in these instances. 



The Harvest Bug (Tetranychus antumnalis), 



is of a brick red colour, and so small as to be scarcely visible to the naked eye. Figure 

 56 represents it in the larval or six-footed form, highly magnified. This insect has 

 peculiarities in habit which distinguish it from those already men- 

 tioned. Though bred upon plants, such as beans and other vege- 

 tables, also on currant, raspberry, and gooseberry bushes, yet 

 when opportunity presents, they will desert these and fasten on 

 animals, manifesting a particular fondness for the human race, 

 especially women and children. The mites fasten upon the skin, 

 particularly where any part of the dress fits closely, and there 

 adhere by their claws so firmly that they can scarcely be detached 

 without violence. Where one of these mites fixes itself a 

 swelling occurs about the size of a pea, sometimes much larger, 

 accompanied with severe itching, the severity of the swelling and itching varying in 

 different individuals. In the chalky districts of Hampshire, England, these pests are 

 especially abundant, also in some parts of Scotland and France ; they do not confine 

 their attacks to mankind, but are troublesome also to horses, cattle, sheep, dogs, cats 

 and rabbits. It is in the larval or six-footed form in which this species is most frequently 

 met with, the perfect eight-footed insect being seldom seen, 



Kirby and Spence mention a similar insect which occurs in Brazil in great numbers. 

 They insinuate themselves into the skin, and occasion intolerable itching, followed by 

 larger swellings which subside in a clay or two. Another species with similar habits 

 occurs in Mexico. 



Trombidium Irritans, 



Fig. 56. 



commonly known as the harvest mite, or "jigger," (fig. 57) is met with in the Missis- 

 sippi valley where it is very troublesome, and produces much irritation in the skin 



wherever it attaches itself. Many species of harvest mites 

 also feed on the leaves of plants, but they do not spin webs. 

 They are also found in damp moss or on moist earth or 

 stones, and vary in size from a pin's point to a pin's head. 

 Those belonging to the genus Trombidium are parasitic in 

 their habits. 



Trombidium Parasiticum 



is a minute blood-red mite which attacks the house-fly. 

 Prof. Riley , in his Seventh Annual Report states that in some 

 seasons in the west scarcely a fly can be caught that is not 

 infested with a number of these blood-red mites clinging tenaciously around the base of 

 the wings. The accompanying figure (58) represents this mite in its immature state. 



Fig. 57. 



Trombidium Holosericeum. 



This speces is found in Europe attacking 

 spider, adhering generally behind the haunches, 

 colour. 



Trombidium Bulbipes 



the lon£-Wo-ed harvest 

 It is of an orange scarlet 



Fig. 58 



is a mite described by Dr. Packard in his Third Report on Injurious and Beneficial Insects 



