384 Rev. 0. P. Cambridge on three new 



Order Acaridea. 



Family Trombidides. 



Gen. nov. Calyptostoma. 



Characters of the Genus. 



Body oblong oval, rather broader before than behind (the 

 fore part somewhat obtusely subangular), upper surface very 

 convex ; epidermis continuous, without any contractions or 

 foldings to indicate the limits of the eephalothorax, caput, or 

 abdomen. 



Mouth-parts apparently very minute, concealed in a deepish 

 circular cavity at the extremity of the fore part. 



Eyes six in number, in three pairs, forming a triangle on 

 the upperside of the fore part of the body ; the apex of the 

 triangle (being the most obtuse of its angles) directed forwards : 

 the eyes of each pair are contiguous to each other, and seated 

 on very slight tubercles. 



Legs short, slender, 7-jointed ; the legs of the first and 

 second pairs and third and fourth pairs, respectively, on either 

 side, have their basal joints in contact with each other, de- 

 scribing nearly a square on the under surface of the body, 

 towards the fore part ; their relative length appears to be 4, 1 , 

 2, 3, though those of the fourth and first pairs are very nearly 

 of the same length, and those of the third pair but little, if any 

 thing, shorter than those of the second. Each tarsus termi- 

 nates with two curved claws, which spring from a cleft at the 

 extremity of its upperside. 



The genital aperture (?) is placed just behind the basal 

 joints of the third and fourth pairs of legs. 



Calyptostoma Hardily sp. n. PI. XIII. fig. 1. 



Adult female, length 2 lines. 



The colour of this interesting Acarid is a uniform reddish 

 yellow (which, however, may possibly, in life, have been a bright 

 red), the legs and genital and anal apertures being light yel- 

 low-brown ; the whole epidermis, which is of a somewhat cori- 

 aceous nature, is thickly covered with minute round punctures, 

 connected, in somewhat regular series, with slight groovings 

 or wrinkles of the skin ; and from each puncture there issues a 

 short, strongish, curved, pale amber-coloured diaphanous bristle. 

 Ten small dark red-brown points, or spots, in so many very 

 slight depressions of the surface, and forming two longitudinal 

 lines, occupy the median line of the upper surface ; from be- 

 hind each of the last two of these points runs a short oblique 

 line or very slight indentation. The underside has two small 



