ASTACID.E. 93 



3. AsTACUS TuowBRiDGii Sfhupson. 



A.ilacus Trowhriilgii Stimpsoii, Proo. Boston Soc. N. II., T. 6, p. 87 (Separat. p. 53). 



Fi^'ures on V\ III. and X. 



Antcnnal lamina, li^. 1 "1, a ; cpistoma, b ; spine of the second joint of the exterior antenna, c. 

 ri. X. Female tvpc. 



Fem. Obosa, olivacea, chclis obscurioribus ; rostro lato loiigo, excavate, 

 parce pimctato. medio obsolete cantiliculato, lateribus jiarallelis, mar- 

 ginatis, cras.-^ioribus ; acumine triangiilari, longo, angusto, acuto, fiisco- 

 corneo, spinis lateralibus validis ; cretis brevioribus, antice spina rejecta; 

 aliaque ad basin cretas spina. Antennis corpore brevioribus modicis, ar- 

 ticiilis duobus l)asalil)us dente externo valido ; antennis internis articulo 

 basali dente inl'ero apieali, lamina valida, trigona rostro breviori, modice 

 lata, margine externo crasso, apice spina longa, acuta. Epistomate tri- 

 angulari ; pedibus maxillaribus externis intus barbatis. Thorace ovato, 

 antice angustiori, densius punctato, lateribus subla^viljus ; linea profiuida, 

 siuuata ; areola lata. Postabdomine thorace latiori, apicem versus dc- 

 crescente, la3vi, angulis segmentorum externis rotundatis; lamina inter- 

 media quadrangular!, apice, angustiori, utrinque spinis duabus validis, 

 rejectis ; parte apieali breviori, fere orbiculari ; lamina laterali vix cos- 

 tata, spina media antemarginali, externaque marginali. Pedibus anticis 

 validis, longis, corpore brevioribus ; chela magna, lata, punctata sub- 

 plana, marginibus subacutis, margine interdum recto subtus excavate ; 

 digitis validis, sub.sinuatis, chela paulo longioribus, apice spinulosis ; digi- 

 to mobili intus basi exciso ; externo digito l>asi intus producto ; utroque 

 intus dentato. Carpo lato, truncato, pnnctato, spina antica interna 

 acuta ; subtus spina media antica. Brachio, subla^vi, margine antico 

 et superiori spinoso, spina anteapicali majori ; subtus biseriatim forte 

 spinoso, utrinque ad articulationem spina valida. Ventre inter pedes 

 quartos la3vi ; annulo transverso, cylindrico. 



Long. Corp. 4; antenn. 3; ped. antic. 3. 



Habitat : Astoria, Oregon ; " near Astoria it occurs sometimes abun- 

 dantly in brackish water." 



I have seen two female types of Mr. Stimpson's, communicated by 

 the Museum of the Soc. Nat. Hist, in Boston. 



This species differs from A. nigresccns in the broad, rounded lateral an- 

 gles of the abdominal segments. 



4. AsTACUS KL.VilATUEXSIS Stinipson. 



Astacus KlamatTiensis Stimpson, Proc. Bost. Soc. N. II., T. G, p. 87 (Separat. p. 52). — Bate 

 Spence. Naturalist in Vancouver's Island and Brit. America, 18G6, T. 2, p. 278. 



Figures on PI III. 

 Antennal lamina, fig. 1C9, a; epistoma, h; .spine of the second joint of the exterior antenna, c. 



Fem. Rostro longo, densius punctate, subplano, medio obsolete 



