17t> KEPORT 1888. 



1. Saccocaris majok, Salter. (Woodcut, Fig. 1.) 



Saccocaris, Salter, 1868. ' Report Proc. Geol. Polytech. Soc. West 

 Eiding of Yorkshire ' ^for 1867), vol. iv. 1868, p. 588. 



Mymenocaris (Saccocaris) major, Salter, 1873. ' Catal. Palseoz. Fossils, 

 Cambridge Museum,' p. 7. Referring to ' Halifax Trans.' 1867,' by 

 mistake. 



The particular specimen which most neai-ly corresponds with the 

 original description, namely, ' a large ovate carapace, strongly emai-ginate 

 behind, and larger than H. vermicauda,' is a relatively large, thin, filmy, 

 compressed valve, 4-j-y inches long and 2 inches high,' suboblong, with 

 nearly parallel dorsal and ventral borders, the former straighter than the 

 latter, which has a slight outward (downwai'd) curve. Obliquely elliptical 

 in front, the acme of the curvature being above the mesial line, thus 

 making the antero-dorsal much shorter than the antero-ventral curve. 

 Apparently blunt or truncate behind, with a gentle outward curve rather 

 above the middle. The exact line of this posterior margin is not clearly 

 seen, owing to its being shredded or frayed otf, thus passing into the sub- 

 stance of the black schistose mudstone ; the valve having been delicately 

 plaited (with the stone) by lateral pressure acting at right angles to its 

 length, and this longitudinal plaiting being transverse to the hind border. 

 The front edge has not been affected nearly so much, having probably been 

 thicker, or even slightly rimmed. This pressure has, perhaps, somewhat 

 elongated the valve, and lessened its original height, besides giving it a 

 gentle undulation, as well as the plaiting (pleating), throughout. 



The valve, slightly hollow, is probably the right-hand valve, showing 

 its inside. Several concentric, irregular, narrow foldings, following the 

 contour of the anterior and antero-ventral border, are apparently due to 

 the compression of the convexity of the valve. 



This specimen, No. 1, at p. 220 of the First Report, and fig. 1 of the 

 accompanying woodcuts, is marked -j^:^, oTfy, in the Woodwardian 

 Museum of the Cambridge University, and was collected by Mr. D. 

 Homfray from the upper part of the Lower Lingula-flags at Caer-y-coed, 

 near Maentwrog. 



This was at first (in 1867) regarded by Mr. Salter as a flat carapace, 

 ' after the manner oi Apus' ; but afterwards (in 1873) he referred it to 

 the bivalved, folded, or Nebalioid forms of carapace, and placed it as an 

 ally of Hijinenocaris, with the name Saccocaris. In shape it differs much 

 from the valves of that genus, as it wants their triangular form, due to the 

 dorsal line forming an angle with the front edge, which slopes rapidly 

 downwards and backwards all along the ventral, to join the posterior 

 margin with a bold, oblique, postero-ventral curve. Differing also remark- 

 ably in size, it must be assigned to a different generic group ; and it will 

 be best to recall the name Salter was at first inclined to give it, namely, 

 Saccocaris. 



2. LiNGULOCARis Saltertana, sp. nov. (Woodcuts, Figs. 6 & 7.) 



The British Museum has lately acquired a fine specimen of one of the 

 old Cambrian Phyllocarids, from the Tremadoc-slate scries. It is a black, 



' H. rermicauda rarely attained more than an inch in length along the back, 8- 

 or 9 tenths of an inch in height, and one and 3 or 4 tenths of an inch in the greatest 

 angular length from antero-dorsal to postero-ventral region 



