600 ox MAinXE OSTRACODA FROM MADEIRA. 



mari;in in a !>hai-plv angular projection : in some cases there is 

 a distinct longitudinal striation, more especially on the ventral 

 surface, and posteriorly near the base of the beak may be seen a 

 series of four nodules, the terminations of small curved carinse 

 (iig. 9). Length 0-4li mm. 



Several specimens were dredged in depths of 50-70 fathoms. 



The surface-ornament of this species varies veiy much : the 

 foregoing description should be taken as belonging to a rather 

 strongly marked specimen. The variations of sculpture seem to 

 depend chieliy on conditions of age and sex. 



CvTHERiDEis SUBULATA. var. CREXUi^TA. noui. u. (Plate XXI. 

 lig. 7.) 



Specimens, of which a figure is here given, seem to be identical 

 Avith a form described in 1874 by myself and the late Dr. Robert- 

 son under tlie name C)/i/ierideis sitbuhta var. fasciata, the 

 varietiil designation having been used on account of the presence 

 of a dark band across the shell. But the type specimens, t^^ken 

 among the Scilly Islands and now in my collection, do not now 

 exhibit any such marking. It is possible that the markings may- 

 have disappeared with exposure to the air, and as the published 

 name is inappropriate. I propose to substitute the varietal term 

 crenulata. In the Madeira specimens, Avhich were taken in a 

 depth of 70 fathoms, the anterior crenulations are much more 

 developed than in those from Scilly, but in all other respects those 

 fiom the two localities are alike. 



Paraboxostoma gracile. sp. n. (Plate XXI. figs. 8, 9.) 



Shell, seen laterally, oblong, subclavate, height equal to more 

 than one-third of the length : extremities rounded off, the anterior 

 narrower and somewhat depressed (fig. 8), dorsal margin evenly 

 but not very strongly aicuate, ventral almost straight : seen from 

 above (fig. 9) extremely compressed, widest in the middle and 

 tapering evenlv to the extremities, Avhich are very acutely pointed, 

 width equal to about one-fourth of the length. Shell-surface 

 perfectly smooth and coloiudess. Length 0-55 mm. 



One specimen only, taken in 70 fathoms. 



Gytherella (?) ovALis, sp. n. (Plate XXII. figs. 11, 12.) 

 Shell, seen laterally, subelliptical, about twice as long as broad 

 (fig. 11); anterior extremity rounded above and below, almost 

 siibtruncate. posterior narrower and somewhat oblique, dorsal 

 margin almost sti-aight. ventral straight, upcurved toward the 

 posterior extremity : seen doi-Siilly the outline is ovate (fig. 12), 

 twice as long as broad, greatest width behind the middle ; 

 extremities well rounded, the anterior much narrower than the 

 posterior. Shell-surface perfectly smooth. Colour white. Length 

 0-42 mm. 



Dredcred in 70 fathoms. 



