126 The Philippine Journal of Science 



practically fused with the thorax, forming (as in the Arachnida) 

 a cephalothorax, into the cephalic part of which (rather than 

 into the sternum) the fore legs are fitted. Only above, behind 

 the eyes, there is a faint trace of a short suture, which does not 

 reach the lateral margins. In Distant's figure of H. indicus the 

 suture between head and pronotum is represented as distinct 

 and curved forward, rendering the head crescent-shaped, but I 

 doubt very much the exactness of this detail in the drawing. If 

 that suture can be made fully visible by boiling the cephalothorax 

 in a solution of potassium hydrate, I think the suture will prove 

 to be straight, and the limits of the head and pronotum should 

 in the above description be conceived accordingly. In Helo- 

 trephes there is on each side of the head near its apex a small 

 acutely triangular piece protruding from under the margin of 

 the head. I have called these pieces subgenal appendices, but 

 I have had no opportunity to prove from what part of the head 

 they take their origin. They are not fused with the gense, as 

 represented in Stal's and Distant's figures. 



CORIXID^ 



Micronecta quadristrigata Bredd. 



Micronecta quadristrigata Breddin, Mitt. Nat. Mus. Hamb. (1905), 22, 

 156. 



Luzon, Laguna, Los Baiios. 



Hitherto known only from Java, where it is common. Bred- 

 din's excellent description renders its identification easy. It is 

 generally a little smaller than the Philippine M. vanduzeei Kirk., 

 the pronotum is longer, the mcsoxyphus is subacute, and the 

 claws of the middle tarsi are shorter. 



In the paper where Kirkaldy described the above-mentioned 

 species he also gave a list of the exotic species of Micronecta 

 known up to that date, but he omitted the East African M. hydro- 

 porina Gerst. (1873) and the Philippine M. proxima Leth. 

 (1877). Distant" describes two species under the names M. 

 thelxinae Kirk, and M. memonides Kirk. ; but these names are 

 printer's errors, corrected in the author's separate copies, the 

 correct names being thelxinae and mnemonides. 



" Fauna Brit. Ind., Rhynch. (1910), 5, ' 



