Chilton. — On Ncio Zealand Freshiuater Crayfish. 249 



Parankphrops planifrons. 



Paranephrops planifrons. 



White, " Zool. Miscel.," p. 79 (1842). 



Dieffenb., " Voy. New Zealand," ii., p. 267 (1843). 



Miers, "Zool. 'Erebus' and 'Terror,'" Crust., p. 4, 



pi. iii., fig. 1 (1874); "Cat. N.Z. Crust.," p. 72 



(1876). 

 Huxley, " Proc. Zool. Soc," 1878, p. 770. 



Paranep hrops tenuicornis . 



Dana, " U.S. Exped.," xiii., Crust., part i., p. 527, 

 pi. xxxiii., fig. 4 (1852). 



Basal scale of antennae large, narrowing abruptly ante- 

 riorly, with deep groove above, reaching as far as or beyond 

 the extremities of the rostrum and of the peduncles of the 

 antennae and antennules. Carapace nearly cylindrical, of 

 same width throughout whole length of the branchiostegites, 

 being a Httle less than one-fourth the total length of body ; 

 smooth, or with small tubercles on sides of branchiostegites, 

 and spines along the cervical groove and elsewhere; two 

 spines on each side of the base of the rostrum. Eostrum 

 elongate, triangular, sometimes depressed, margins raised and 

 usually with four teeth on each side, under surface keeled 

 and usually with two teeth. Median ridge behind the rostrum 

 clearly marked in front, arising slightly in front of the two 

 lateral ridges of the rostrum, and reaching about half-way 

 from its anterior extremity to the cervical groove, disappearing 

 gradually. Anterior portion of the epistoma triangular, flat, 

 narrowing anteriorly, and ending in a sharp spine. Great 

 claws long, slender, propodos (without fixed finger) about 

 twice as long as the carpus and about two and a half times 

 as long as broad, whole limb densely spined ; spines on pro- 

 podos arranged more or less regularly in longitudinal rows, 

 and with occasionally a few scattered hairs. Pleura of abdo- 

 minal segments rather pointed at the infero-posterior angle, 

 anterior edge longer and more convex than the posterior and 

 fringed with setas, posterior edge sinuous and scarcely curving 

 forwards. 



Length of largest specimen, 5-25in. 



Habitat. North Island generally, and the north-western 

 portion of the South Island as far south as Grey mouth. 



Paranephrops neo-zelanicus. 



Astacus zealandicus. 



White, "Proc. Zool. Soc," p. 123 (1847) ; "Ann. and 

 Mag. Nat. Hist." (ser. 2), i., p. 225 (1848). 



