108 PROCEEDINGS OF THE ACADEMY OF 



nato ; palpi nonnihil gracilibus, subelongatis ; manibus parvissiniis ; digi- 

 tis valde elongatis, gracilibus, curvatis ; cauda gracile, nonnihil elongata ; 

 spiculo modice longo, valde curvato, sine spinulo basili ; pectinis dentibus 

 fere 18. 



The cephalothorax is medianly canaliculate, and anteriorly broadly but 

 very shallowly emarginate. The lateral eyes are arranged in a straight or 

 nearly straight series. The palpi have their surface quite rough, and are 

 somewhat elongate and slender. The second article has four minutely crenu- 

 late crests, besides minute tubercles on its anterior face. The third has five 

 ridges, besides larger tubercles on its front surface. The anterior aspect of the 

 hand is very convex. The posterior border is ornamented by an obsoletely 

 crenulate ridge. The opposing margins of the fingers are armed with obliquely 

 longitudinal imbricated rows of minute teeth, with a series of distant larger 

 ones on either side. The caudal surface is rough. The first joint has very 

 minutely denticulate superior, supero-, median, infero-lateral, and inferior 

 ridges. The next three articles have the same crests, excepting the median 

 lateral. There are generally no distinct ridges on the penultimate segment. 

 The last joint is short, and very narrow, but quite thick. Its superior aspect 

 is not complanate ; its inferior is strongly convex. The lower surface of the 

 tail is generally marked with a median longitudinal stripe. The sternal plate 

 is triangular, with its apex truncate. 



Length of body, J> 7 lines, $ 8 lines : of tail, ^ 13 lines, $ 12 lines. 



Hab. Lower California. Smithsonian Museum. 



B. HIRSUTUS. 



B. brunneus ; palpi, pedibus caudaque dilute aurantiacis, longe pilosis ; 

 cephalothorace lato, margine antico non solum baud emarginato sed etiam 

 convexo ; oculis lateralibus in serie valde curvata dispositis ; palpibus crassi- 

 bus, marginibus nonnihil crenulatis ; manibus modice tumidis, obsolete sep- 

 templicatis, marginibus posticis anticisque tuberculatis ; digitis valde elongatis, 

 robustis, curvatis, obsoletissime plicatis ; pectinis dentibus 25 30 ; abdomine 

 nonnihil laeve, haud carinato ; spiculo sine spinulo basali. 



The common tint of the dorsum is a very dark reddish-brown, but it varies 

 greatly, in some specimens being as light as the legs, in others even olive. In 

 the typical pattern, whilst the penultimate caudal segment is of the same 

 reddish-brown as the body, the terminal is very light. The cephalothorax is 

 broad, and has its surface minutely granulate. The median furrow is strongly 

 pronounced, and is intersected by three transverse crosses. The most anterior of 

 these crosses is at the position of the median ocelli ; the most posterior just in 

 front of the hinder margin. Rarely these are somewhat obsolete, and some- 

 times tbey are slightly oblique. The opposing edges of the fingers are armed 

 with obliquely longitudinal imbricated rows of small teeth, with a series of 

 larger distant ones on each side. The surfaces of the abdominal scuta are 

 quite smooth, but their posterior borders are tuberculate. Anteriorly they 

 are impressed with two crescentic linear furrows. The legs are compressed and 

 hairy ; their edges are more or less crenulate. The tail is long, massive, 

 rough and very hairy. At the proximal end of each of the first four joints, 

 there is a pair of broad, thin, minutely denticulate articular processes. On 

 the distal extremity of the fourth there is a nondenticulate pair. The su- 

 perior, supero and median lateral crests of the first four articles are strongly 

 but irregularly crenate. The median is evanescent, on each, anteriorly. The 

 inferior and infero-lateral ridges are smooth on the two anterior joints, on the 

 third they are slightly, on the fourth distinctly crenate. The supero and me- 

 dian lateral crests of the penultimate segment are strongly crenulate ; the 

 infero lateral and median inferior strongly denticulate. The last joint is short, 

 swollen and very hairy. Its articular processes are large, but not dentate. 

 Its superior surface is triangular, smooth and complanate, or even depressed ; 

 its inferior is tuberculate, and traversed by two grooves on each side. 



[April, 



