Mr. MacLeay on some neiv forms o/Arachnida. 3 



joint vertical, short, subcorneal, with the second joint or 

 fang small, curved, acute, and of the same colour as first 

 joint. 



Eyes only two, placed close together towards the fore part of 

 cephalothorax. 



Maxillce conspicuous, subquadrate, bent round the mentum 

 and having their apex obliquely truncated. 



Maxillary palpi having the first joint very short, the second 

 joint obconical and elongate, the third short and bent, 

 the fourth straight, obconical, and longer, the fifth or last 

 thick, oval, and hirsute. 



Labial palpi pediform with seven joints. 



Mentum separated from the sternum by a transverse furrow ; 

 longer than broad with its frontal edge semicircular. 



Head not distinct from thorax. Cephalothorax subtranslucid 

 with convex back without hair, obovate, narrowing gra- 

 dually towards the front, which is rounded. Its tegument 

 is subcrustaceous, while that of the abdomen is membra- 

 naceous. This abdomen is a prolate spheroid terminated 

 by six spinners of which two are inconspicuous and two 

 are very prominent. Sternum twice as long as broad, 

 oval, flat, and crustaceous. Feet like the labial palpi 

 translucid ; the penultimate pair being the shortest. Un- 

 gues short, pectinated at base. If there be a third unguis 

 it is evanescent. 



Sp. 1. Nops guanabaco;£. — Nops sanguineo-rubra, palpis maxillavibus 

 articulo ultimo crasso obscuvo hirsuto pilis canescentibus ; cephalotho- 

 racis macula oculifera parva nigra, pectore punctata piano ; abdomine 

 obscuro hirto, fusulis paliidioribus ; pedibus versus apicem hirtis ; un- 

 guibus nigris. 



Long. 5 lin. 



The trivial name of this remarkable spider will serve to com- 

 memorate Guanabacoa, the place where first I found it, a place 

 in which I long resided, devoting many delightful hours to the 

 science of natural history. The genus Nops is easily known 

 from all other spiders hitherto described by having only two 

 eyes. These are round, black, and when alive very brilliant ; 

 but they have no iris. In the species Nops Guanabacoce they 

 are set in the middle of a black spot, which is on the fore part 



b2 



