No. 2.] SPIDERS OF THE MARPTUSA GROUP. 103 



The cephalothorax is moderately high, and is flat above, 

 the cephaHc and the anterior thoracic parts being on the same 

 plane. The widest point is considerably behind the dorsal 

 eyes, and it is sensibly contracted both in front and behind. 

 The sides are nearly vertical in the cephalic part, but round out 

 quite widely in the thoracic. The thorax is flat for about one- 

 half its length, and then rounds off and falls rather steeply to 

 the posterior margin. The quadrangle of the eyes is one-third 

 wider than long, is almost equally wide in front and behind, 

 and occupies two-fifths of the length of the cephalothorax. 

 The first row is straight, or curved downward, with the eyes all 

 close together, the middle being fully twice as large as the 

 lateral. The second row is nearer the first than the third row. 

 The third row is nearly as wide as the cephalothorax at that 

 place. The abdomen is rather long and is pointed behind ; it 

 is rounded, not fiattened. The labium is about as long as wide. 



The species upon which we found this genus seems to lie 

 between Sadala and Balmaceda. It is too large and heavy for 

 the former genus and is not of the right shape for the latter. 

 In Balmaceda the first row of eyes is straight and the cephalo- 

 thorax is flat through nearly all its length ; in Omura the first 

 row is curved downward and the posterior slope of the cephalo- 

 thorax begins at about the middle of the thorax. In Sadala 

 the middle eyes of the first row are relatively larger than in 

 Omura. 



The shape of the abdomen is like that of Mendoza, but the 

 body and legs are much smaller and more delicate. Mendoza, 

 moreover, is found in Egypt, and Omura in Brazil. 



OMURA CRUENTA SP. NOV. 



Plate X., Figs. 2— 2c. 

 9 . Length, 7.6. Length of cephalothorax, 2.6 ; width 



of cephalothorax, 2. 

 Legs, 4812, the third and first being nearly equal. 

 The first and second pairs are stoutest. 

 This is a medium-sized, handsome red spider. The falces 

 are moderatelv long and stout and are vertical. The first and 



