MOLLTJSCA. 95 



sulci cutting across them. The margin of the valves within is den- 

 ticulate everywhere except down the posterior dorsal slope, the 

 denticles on the edge of the lunule being finer and closer together 

 than elsewhere. The pallial line is posteriorly nearly straight, or 

 even a little incurved just before the commencement of the sinus, 

 which is rather deep. The interior is generally somewhat rosy, 

 especially towards the beaks. 



8. Cytherea (Caryatis) coxeni. (Plate VII. figs. A-A2.) 



Shell small, inequilateral, subtrigonally oval, white, variegated 

 with pale zigzag brown or reddish lines forming an irregular broken- 

 up network. Anterior dorsal margin straightish, much descending, 

 sharply curving at the end into the upturned ventral outline. 

 Posterior slope much longer^-somewhat arcuate and less oblique than 

 the anterior. Hinder extremity produced, roundly acuminated. 

 Lower margin widely curved, about equally ascending at both ends. 

 Umbones small, well curved over towards the front. Lunule long- 

 ish heart-shaped, a little sunken, slightly elevated along the middle, 

 and defined by an impressed line. Area indistinct. Surface of the 

 valves finely sulcate-striated, the intervening lirae being somewhat 

 rounded, much crowded at the sides, some of them not extending 

 quite to the lateral outlines, especially posteriorly. Central cardinal 

 tooth of the left valve thick, triangular, the two others slender and 

 lamellar ; posterior in the right valve elongate, the central erect, 

 conical, free. Posterior muscular scar nearly circular, the anterior 

 narrower, ovate. Pallial sinus moderately deep, rather wide, squarely 

 truncated at the end. Length 13 miUim., height 10^, diameter 7. 



Hah. Port MoUe, Queensland, 14 fms. 



This species I am unable to identify as the young stage of any 

 known larger species. It apparently becomes more pointed behind 

 as it increases ; so that if it be the early growth of the species, the 

 adult form will, be much produced at that part. 0. minuta, Koch, 

 has no coloured pattern and a different pallial sinus. 



The form of this species resembles very closely that of C. pura, 

 Deshayes, a species found at Callao in South America. It is, how- 

 ever, more strongly concentrically Urate, is ornamented with pale 

 brown zigzag lines and dots, and the form of the pallial sinus is 

 quite different. 



9. Cytherea (Caryatis) albina. 



Lamarck F ; Homer, Monogr. Venus, Nbvitat. Conch, p. 87, pi. 23. 

 figs. 5-6 b. 



Hah. Port Molle, Queensland (Goppinger). 



The shell from the above locality agrees with Rdmer's determi- 

 nation of this species ; and two specimens from Cape York in the 

 Museum, named Z». huUata of Sowerby by Deshayes (Cat. Conch. 

 Biv. p. 70), are also referable to it, for they have not the straightish 

 ventral margin of that species. 



