122 DK. C. CHILTOX ON THE 



perhaps, a little misleading. In making it he appears to have counted the basos as 

 one joint and all the terminal part as the second. He did not reckon in the coxa, which 

 is usually more or less distinct, and he included the ischium, which is also \isually 

 distinct, Avith the terminal portion which generally shows indications that it is composed 

 of three or four joints. In cases of this kind the actual number of joints is less 

 important than the comparative sizes of those that are represented, though of course it 

 is not easy to express this in brief language. 



I include under this family the genera Sci/pl/ca; Dana, ActcBcia, Dana, and Scypho- 

 niscus, gen. nov., all of which are represented in JS^ew Zealand. It will, I think, also 

 include Scyphacella, S. I. Smith, and Actoniscns, Hayer. both of which are discussed in 

 another part of this paper, and Philomfria manna, Chilton, which Stebbing has rightly 

 said cannot remain under PhUougria, probably also belongs to this family, though as yet 

 I have not had time to examine it sufficiently to say whether it can be referred to any 

 of the genera mentioned or not. 



It may be worth while to point out that Kinahan, in his excellent " Analysis of 

 Certain Allied Geuera of Terrestrial Isopoda," published in 1857, appears to have 

 recognised the fact that Seypl/ax and Act(ccia probaloly formed types of separate 

 families, though owing to the great difference between thein in general appeai-ance, he 

 evidently did not think of placing them both in the same family *. The three genera 

 that I have included in this family all agree pretty closely in the mouth-parts and 

 pleopoda, and I am inclined to attach comparatively little importance to the external 

 form of the body. 



Genus 1. Scyphax, Dana. 



Scyphax, Dana, U. S. Explor. Exped., Crust, ii. p. 733 (1853). 

 Smjphax, Miers, Cat. New Zealand Crust, p. 101 (1876). 

 Sci/jjJiax, Budde-LiuKl, Isopoda Terrestria, p. .231 (1885). 



Generic descr'qjtion. — Body somewhat convex, not cajjable of rolling into ix ball; 

 epimera moderately developed. Metasome not abruptly contracted, last segment not 

 much produced. Eyes large, of very many ocelli, crescent-shaped, occupying the sides 

 of the cephalon. Antennse with the flagellum 3- or 4-jointed. Second maxilla with 

 the outer margin a little angularly produced near the base. Mandibles with few 

 penicils behind the cutting part. Legs increasing in length posteriorly. Opercular 

 plates of pleopoda without any air-cavities. Uropoda exposed, inner branch arising 

 only slightly in front of the outer. 



Remarks. — I have ventured to give a new diagnosis for this genus which was 

 established many years ago by Dana for the single species S. ornatns. In 1876, Miers 

 added a new species, S. intermedius, but this, as shown below, proves to be the same as 

 S. ornatus. 



Another species, S. setiger, from New Caledonia, was added in 1885 by Budde-Lund, 

 who gave a diagnosis of the genus based mainly on external characters, and considered 



* Natural History Ecvicw, iv. Proceedings of Societies, pp. 274 & 275 (1857). 



