898 ME. p. O. PICKAED CAMBRrDGE ON [NoV. 29, 



margin; the fourth pair elongate and very deep, impinging on 

 the margin. 



The spinners as in Avicularia. Tarsal claws 2, those of the first 

 pair of legs with 3 minute teeth on the inner margin in tlie centre, 

 of the fourth pair with 2 minute teeth in the same position. 



Upwards of ten specimens, all of the female sex, many being 

 immature, were taken by Dr. W. Ince on his estate, Dik-Mat- 

 Karo, in Trinidad. A single female in the British Museum 

 collection, already described by me as Santaremia longipes, 

 was taken by C. Taylor, Esq., in Trinidad ; and an adult male was 

 recently received from T. Potter, Esq., of the Port-of- Spain, 

 Trinidad. 



These specimens have proved of exceeding interest, since they 

 furnish us with the first case of a Theraphosid (other than a 

 Diplurid) belonging to the Neotropics possessing the stridulating- 

 organ on the mandible and the coxa of the pedipalp. I had not 

 noticed this orgau when I described Mr. Taylor's specimen under 

 the genus Santaremia ', and the characteristic fringe had been 

 considerably worn from the legs. 



But a still more interesting discovery perhaps lies in the fact 

 that these specimens are also undoubtedly identical with the 

 Spider described by Mr. E. I. Pocoek as Psalmopceus camhridgii, 

 the locality being doubtfully given " East Indies." It seems 

 probable that this locality was an error on the part of the 

 collector, and that Trinidad, or perhaps mora broadly " the "West 

 Indies," constitutes the headquarters of the species. 



This identity being established, Santaremia longipes becomes a 

 synonym of Psalmopceus camhridgii. The further interesting point 

 arises as to whether this stridulating-organ has been independently 

 developed in this one Spider amongst the Theraphosidae of the 

 Neotropics, or whether Psalmopceus is closely allied to those 

 Oriental forms of Theraphosidae which, without exception, possess 

 the stridulating-organ. 



In one particular character, however, Psalmopceus differs from 

 the Oriental forms. In the latter the males have no spur or spurs 

 at the apex of tibia i. beneath, whereas the male of P. cambridgii 

 from Trinidad possesses two. 



In addition to the above examples, an adult male of a Spider 

 taken in Costa Rica, belonging to the same genus, but probably of 

 a different species, was kindly sent me by M. Simon. 



Another Spider, an adult male, was also sent me by the same 

 arachnologist under the name Tapinaucfieni^is plumipes (C. Koch) 

 from Sm-inam. This Spider, very much resembling the males from 

 Trinidad and Costa Rica, has, however, no trace of the stridulating- 

 organ. This fact would tend to estabhsh the distinction between 

 the genera Tapinauchenius and Psalmoj^oeus, much though the 

 Spiders resemble each other in general characters. I may remark 

 that Tapnnauchenius sancti-vincentii ( Walck.) — sec. Simon — does not 



' P. Z. S. 189G, p. 749. 



