ASTACmiE. 73 



excision; the example is otherwise similar to Cimmurds; nevertheless, 

 it possibly belongs to a different species. 



C. immHuis is a very interesting species ; by its conical, short, and 

 toothless rostrum it is allied to the group of C. Bartotm, by the ab- 

 dominal legs of the male to the group of C. affirm. I have not seen 

 young specimens ; they, perhaps, possess lateral spines. 



Cat. No. 188, Lawn Ridge, 111.. Mr. C. Ordway. Male. Fern. Spec. 5. 



Cat. Xo. 1841, Belleville, 111. Male. Spec. 1. 



Cat. Xo. 301, Huntsville, Ala. Male. Spec. 1. 



Cat. Xo. 1842. Beaufort. X. C. Mr. Bickmore. Fern. Spec. 1. 



23. Caubarus extraxeus Hagen. 



Figures on PI. I. and III. 



First abdominal legs of the male : 



second form, fig. 88 in front ; fig. 89 outside. 



Antennal lamina, fig. 156, a; epistoma, b ; spine of the second joint of the exterior an- 

 tenna, c. 



Mas. Eostro lato, duplo vel triplo-longiori. laevi, excavato, margini- 

 bus punctato-lineatis, subparallelis vel subconvergentibus, utrinque ad 

 apieem fortiter sinuatis ; acumine longo, acuto, utrinque dente brevi, 

 acuto ; cretis parum elevatis, parallelis, sulcatis, spina acuta antica. 

 Antennis vahdis iliasis modo exstat), articuhs duobus basalibus dente 

 externo acuto, antennis internis articulo basali dente infero acuto; la- 

 mina rostri longitudine, modice lata, margine externo late inflate, apice 

 spina acuta longiori. Epistomate brevi. lato, antice obtuso. rotundato, 

 angulis lateralibus acutioribus ; pedibus maxiUaribus extends intus 

 barbatis. Thorace leviter ovato, densius punctato-eiliato. lateribus 

 granulosis, scabris; linea profunda, subfissa, utrinque spina valida acuta; 

 spina antica infera ad anteunarum basin; areola lata, plana, punctata. 

 antice posticeque paulo dilatata. cephalothorace margine antico ad basin 

 anteunarum loco anguli dente parvo acuto. Postabdomine thoracis lati- 

 tudine, paulo longiori. parce punctato, segmentis antepenultimis angulo 

 laterali subrecto; lamina intermedia utrinque bispinosa, parte apicah 

 breviori. rotundata. Pedibus anticis modicis ; chela magna, lata, depres- 

 sa. densius punctato-ciliata ; margine interno longo, subrecto, biseriatim 

 tuberculato-dentato; digitis vahdis, planis longioribus, costato-lineatis, 

 intus dentatis, basi subtus barbatis. Carpo lato, oblique truncato, parum- 

 punctato. spina interna media majori, ahaque basali brevi; subtus spinis 

 duabus anticis vahdis. Brachio longiori. laevi, spinis duabus anteapicah- 

 bus vahdis, oblique positis, subtus spinis acutis biseriatis, spina ad arti- 

 culationem utrinque valida. Pedibus tertiis articulo tertio unguiculato; 

 pedibus quartis capitulo basali ovato, parvo. (Forma I. mihi invisa.) 



Forma II. Pedibus abdominahbus basi articulatis. vahdis, brevibus, 

 contortis ; parte interna cylindrica, brevi, apice acutiori recurva ; parte 



