314 Proceedings of the Royal Society of Victoria. 



sandstones of the Moonee Ponds Creek. They are undoubtedly 

 remains of phyllopodous Crustacea allied to, if not identical 

 with, Ceratincari'S, and seem to be casts of the strong- abdominal 

 appendage or style. 



Some of the specimens show a fine striation running obliquely 

 to their length and passing over the ridge, uv arranged in a V- 

 shaped pattern, such as is often seen on the appendages of 

 phyllocarids. 



Similar fragments have been figured by Barrande.^ The 

 style shown in the figure of Ceratiocaris papilio, Salter, given 

 by Jones and Woodward'^ bears a close resemblance to our 

 specimens. 



Locality and Horizon. — Moonee Ponds Creek, near Fleming- 

 ton (" Royal Park "). Silurian (Melbournian). 



Family Rhinocaridae. 

 Genus Ditliyrocaris^ Scouler. 



Dithyrocaris praecox, sp. nov. (PI. XVIL, Fig. 3.) 



Description. — Carapace subquadrate ; anterior notch of me- 

 dium size compared with known species, angular ; posterior 

 border angulated, with evidence of posterior spines. Surface 

 of carapace numerously pitted, especially along the ventral 

 borders. Meso-lateral ridges, apparently smooth, strong, and 

 sinuously curved. Appendages, one stout caudal joint, ■n'ith 

 spinous terminations. 



Dimensions. — ^Length of carapace, 17 mm. ; approximate 

 width, 1.3 mm. ; length of caudal appendage, 9 mm. 



Observations. — This specimen, although somewhat crushed 

 and relatively displaced, shows decided affinities with the genus 

 Dithyrocaris. The hinge-line, so far as can be seen, is com- 

 parable with that genus in having a rugose edge. In its 

 medium-sized angular anterior notch and circular surface pittings 

 this species resembles D. testudinea, Scouler sp., from the 



1 Syst. Sil., vol. i., Supplement, 1872, p. 459, pi. .xxxiii., figs. 25, 25a. 



2 Brit. Pal. Phyllopoda (Phyllotarida), pt. i. (Pul. Soc. Mod.), 1888, pi. \ii , fijf. 1. 



