860 MOTfS. E, SIMON ON THE SPIDERS OF ST. VINCENT. [NoV. 16, 



the ubiquitous Mus rathis. The rats normally inhabiting ships 

 are not, as is commonly supposed, Mus decumanus, but Mus rattus, 

 and in most cases are of the grey variety of that auimal, with 

 white belly, though the black form may often be caught in the 

 same ship as the grey. For instance, Mr. F. O. P. Cambridge 

 caught two rats on board the Siemens cable-ship up the Amazons, 

 one of which is nearly a typical Mus rattus, while the other almost 

 exactly matches the specimens sent over by Mr. Waite as Mus 

 arhoricola. The habits of the latter, as here recorded, are in 

 agreement with this supposition, for all the world over M^is rattus 

 takes to roofs ' and trees on meeting its formidable rival Mtis 

 decumanus, to which it leaves the gutters and cellars. This relative 

 distribution of the two species has been frequently noticed in the 

 East-end of London, near the Docks, where ship-rats are particu- 

 larly common. 



The fact that Mr. Waite knows of the occurrence of " Mus arhori- 

 cola " only in and close to a large seaport town hke Sydney is 

 also, of course, confirmatory of the above opinion. — O. T.] 



4. On the Spiders of the Island of St. Vincent.— Part III." 



By E. Simon'. 



[Eeceived August 20, 1897.] 



Ordo AEANE^. 

 Familia Theeidiid^. 

 Argyeode^. 

 Aegtrodes cancellatus Hentz. 

 EhomphjEa (Ariamnes) paradoxa Taczanowski. 

 Ariamnes longissimus Keyserling. 



EpISINBjE. 



Janulus ertthrophthalmus E. Sim., P. Z. S, 1894, p. 525. 

 Episinopsis simplicifrons, sp. nov. 



2 . Long. 3 mm. — Gejjhalotliorax nigricans, subtiliter coriaceus 

 et opacus, vix distincte rufulo-variegatus. Oculi antici in 

 lineam leviter procurvam, medii majores convexi, inter se distantes 

 sed a lateralibus contigui. Ocidi jpostici cequi, sat magni, in 

 lineam valde recurvam, inter se fere aquidistantes, spatiis inter- 

 ocidarihus ocidis haud latiorihus. Area mediorumsuhparallela, 

 paulo longior quam latior, pone oculos anticos leviter convexa 



1 Cf. Mus " tectorum," Savi. 



2 For Part I., see P. Z. S. 1891, p. 549 ; for Pnrt II., P. Z. S. 1894, p. 519. 



3 Communicated by Dr. D. Siiaup, F.R.S., F.Z.S., on behalf of the Committee 

 for Investigating the Faima and Flora ot the West-Indian Islands. 



