Notes on Tyrogly^liidse. By A. D. Michael. 29 



curves forward and downward. There is a much shorter chitinous 

 knob in the same position on each tarsus of the third pair. 



Abdomen. Shghtly narrower posteriorly than anteriorly, 

 dorsal surface rounded, lateral margin somewhat undulated. The 

 anterior margin almost straight and well marked off from the 

 cephalothorax. The true hind margin is rounded, but only the com- 

 mencement of it can be seen, from the dorsal surface being hidden 

 by a broad chitinous, rounded, shelf-like projection which is rather 

 narrower than the true hind margin of the body, and considerably 

 darker in colour. This chitinous piece is on the dorsal level, the 

 abdomen curving up to it from the ventral surface. The chitinous 

 shelf carries four long, diverging, flexible hairs, inserted on its 

 under surface a little within the margin. These hairs project 

 backward. The anus is a terminal median slit, but passes on to the 

 ventral surface ; and on each side of it, on the vertical part of the 

 hind margin, is a large copulative sucker, which can be exserted or 

 retracted ; when projected, the real hind margin is also inflated, 

 and then the chitinous shelf appears narrow. The genital organ 

 is placed very far back, not far from the anus, and consists of a 

 short chitinous intromittent organ within a narrow chitinous ring 

 (flattened at the base). The epimera of the abdominal legs are 

 biforked, one branch arising from each proximal angle of the 

 coxa, and joining after a length about equal to their original 

 distance apart, so that they enclose an equilateral triangle, from the 

 point of which a curved, chitinous blade runs forward and inward, 

 but does not reach the median line. The fourth epimeron is also 

 slightly biforked at the inner end. The lateral margin of the 

 abdomen carries three or four long flexible hairs. 



Female. 



Average length about • 47 mm. 



„ breadth „ -12 „ 



„ length of legs (1st and 2nd pairs) • 7 „ 



The principal difierences of the female from the male consist 

 in the much greater size, the smaller projjortionate length of the 

 legs, the entire absence of the chitinous shelf at the posterior 

 margin of the abdomen, and of course the position of the sexual 

 organ. There are also the following minor differences. 



Cephalothorax. The rostrum is slightly broader and more 

 powerful, and the mandibles greatly stronger and larger than in 

 the male, the other trophi also are better developed. 



Abdomen. The hind margin is rounded ; the anus is protected 

 by two thin, chitinous blades, which are ordinarily closely pressed 

 against each other, and form a small median projection when 

 viewed from the dorsal aspect, from beneath they rather form an 



