146 BULLETIN 12d, UNITED STATES NATIONAL MUSEUM 



probability, that certain forms are specifically distinct, while others 

 showing minor but rather constant differences, not correlated with 

 geographical distribution, are designated as formae. 



KEV TO THE AMERICAN SPECIE3 OF THE GENUS EPIALTUS 



A^ Propodites of ambulatory legs without a tooth on lower surface. 

 B'. Rostrum simple, margin entire or nearly so. 

 C Rostrum not dorsally carinate. 



D^ Tip of rostrum either rounded or truncate, not spiniform. 

 , E'. Carapace with a very shallow sinus between lateral lobes. Hand 

 of male high. Preorbital angles obtuse. Tip of rostrum rounded. 



bituberculatus, p. 148. 

 E^. Carapace with a deep sinus between lateral lobes. 

 F'. Rostrum narrow. Hand of male elongate. Preorbital angles 

 sharp. 

 G'. Rostrum very narrow, sides parallel, tip subtruncate, with 



faint indication of two lobes longirostris, p. 151. 



G^. Rostrum a little wider, tip slightly arcuate in dorsal view. 



longirostris forma portoricensis, p. 151. 



F^. Rostrum broad. Branchial lobe acute, hepatic lobe rounded. 



G'. Legs long and very slender, especially the first pair. Postor- 



bital part of carapace nearly one and a half times as wide 



as long bermudensis ^^ 



G^. Legs stout and shorter than in G^ Postorbital part of carapace 

 about one and a fourth times as wide as long. Margin of 



hepatic lobe crenulate crenulatus, p. 158. 



D^. Tip of rostrum spiniform below. Upper crest of palm laminiform. 



sulcirostris, p. 150. 

 C^. Rostrum dorsally carinate. Carapace widest at hepatic regions. 



Cardiac region conical kingsleyi, p. 152. 



B^. Rostrum either bilobed or bidentate. 



C. Rostrum short; carapace in front of anterior margin of hepatic lobe 

 much shorter than behind the same margin; hepatic lobe much larger 

 than branchial lobe. 

 D^ Hepatic lobe directed more or less forward; rostrum oblong; no tuft 



of hair on propodites of legs hiltoni^ p. 156. 



D^. Hepatic lobe not directed forward; rostrum narrowing anteriorly; a 



tuft of hair on propodites of legs dilatatus, p. 153. 



C^. Rostrum long; hepatic and branchial lobes more nearly of a size; a 

 tuft of hair on propodites of legs. 

 D*. Carapace widest across branchial regions; length in front of hepatic 

 lobes nearly as great as behind the same line. 



dilatatus forma elongata, p. 154. 



D^. Carapace about equally wide across hepatic and across branchial 



regions; length in front of hepatic lobes greater than, or nearly as 



great as, behind the same line minimus, p. 155. 



A^. Propodites of ambulatory legs with a tooth on lower surface. 



Bi. Rostrum triangular, simple. Carapace subtriangular.brasiliensis, p. 149. 

 B2. Rostrum oblong, with bilobed tip peruvianus, p. 157. 



Species on both sides of the continent: bituberculatus. 



** Not American. Verrill, Trans. Connecticut Acad. Sci., vol. 11, 1901, p. 16, nl- 1, fig- 1- 



