3 1 6 Miscellanea. . 



the limestone of Wagamee, N. S. Wales, and also in the limestone 

 of Wollamhoola, N. S. Wales. 



CRUSTACEA. 



{Entomostraca.) 



Bairdia curtus (M'Coy), Synop. C. L. Foss. PI. XXIIL fig. 6. 



This little creature is perfectly identical with those I have 

 described and figured, from the lower limestone of Kildare, in the 

 * Synopsis of the Carb. Limestone Fossils of Ireland.' 



Mr. Morris, in Count Strzelecki's work, has noticed a Bairdia 

 which he says is intermediate between my B. gracilis and B. curtus, 

 being more slender than the latter ; but his figure is greatly more 

 gibbose, so that I am uncertain whether his B. affinis be really 

 distinct or not. At any rate there can be no doubt with regai-d to 

 the present examples, which are from the shale of Dunvegan, 

 N. S. Wales. 



Cythere impresm (M'Coy), Synop. C. L. Foss. PL XXIIL fig. 16. 



This is another species which I have described from the shales 

 at the base of the carboniferous series in Ireland, and from the 

 complexity of its form is, if possible, a still more positive identi- 

 fication than the last ; the agreement in outline, central hollow, and 

 its little marginal tubercle, &c. being absolutely perfect, and admit- 

 ting of no doubt. It is certainly very curious to see those two 

 genera and species of minute Crustaceans occurring together in the 

 shales at the Antipodes just as we see them in our own lower car- 

 boniferous beds. 



Occurs with the B. curtua in the shale of Dunvegan, N. S. Wales, 



{Trilohita.) 

 Brachymetopus (M'Coy), new genus. 



Gen. Char. Cephalothorax truncato-orbicular ; limb narrow, pro- 

 duced backwards into flattened spines ; glabella smooth, cylin- 

 drical or ovate, about twice as long as wide, not reaching within 

 about its own diameter of the front margin ; one pair of small, 

 basal, cephalothoracic farrows, or none. Eyes reniform, in the 

 midst of the cheeks (? smooth); eye-lines unknown. Surface 

 strongly granulated ; one tubercle on each side of the anterior 

 end of the glabella, the marginal row and a circle round each 

 eye being larger than the rest. Body-segments unknown. 

 Pygidium nearly resembling the cephalothorax in size and 

 form, rather more pointed, strongly trilobed, and with a thickened 

 prominent margin ; axal lobe about as wide as the lateral lobes, 

 of about seventeen narrow segments ; lateral segments about 

 seven, divided from their origin, each terminating in a large 

 tubercle at the margin. 



The minute Trilobites for which I propose the present genus are 

 very distinct in habit from those of other genera, and as two or three 

 species are now known, it seems desii'able to place them togethex' 

 under one name. They are the smallest perfect Trilobites known, 

 from two to three lines being the greatest width they have been; 



