92 



REPORT — 1884. 



8. Apt.jclioims, sp. 



In the University Museum at Cambiiilgc is a small tliscoidal Apti/. 

 chupsis (laV'lled ' .1. unatlna '), which is subcircuhir or oblately circular 

 (that is, transversely oval, with a broad elliptical contour). It is rather 

 convex ; the sutural lino remains raised along the somewhat depressed 

 aarfaco ; and perhaps the test is now rather broader than at first, but not 

 far from the orijjfiiial si/.o and shape. Concentric ])arallel lines ornament 

 the surface ; nuchal suture at an anjrle of about 0(1'' ; (ho notch occupying 

 about a third of the length of the shield, which was -0 mm. long by 

 26 mm. in width. 



Collected by Mr. ^larr, F.G.S., in he Bi-alhay (Lower Coniston) 

 Flags, at Nanny Lane, Troutbeclc, Winilerniere. 



A similar form from iloffat has been fijrurcd by Mr. James Dairon in 

 the 'Trans. Geol. Soc. Glasgow,' vol. vii. part 1, 188;?, pi. 7, f. '-Vl. 



There is a somewhat similar oblately (circular Ajiliiiltopsis in the British 

 Museum, from the Gala Group, Gala Hill, (ialashiels ; but it is smaller, 

 and has a relatively larger notch. It seems to have been mm. in length 

 (fore and aft), and 12 mm. wide. The slope of the nuchal sutui'e is 

 about r)0°, and the notch reaches half-way down the tost : this, however, 

 has suffered considerable vertical pressure. 



No Goniatitos have been found witli any of tlie abovn. 

 [N 15. — The new species will receive names wlien they are figured.] 



XI. Pkltocakis, Salter, 18G3. Dithyrocaru, Salter, 1852, 'Quart. Jour. 

 Geol. Soc' vol. viii. p. 391 ; Ceratiocaris, Salter, 1800, ' Ann. Mag. 

 Nat. Hist.' ser. 3, vol. v. p. 161 ; Fdturaris, Salter, 1803, ' Quart. 

 Jour. Geol. Soc' vol. xix. p. 87. 



This Phyllopod has a discoidal, round or oval, tripartite shield, with 

 a straight median dorsal suture, and a curved nuchal suture, which, giving 

 way after death more easily than the other, has left in some instances a 

 rounded, elliptical, or semi-oval cephalic notch in the shield. The separate 

 lateral pieces of the test have an inner concave curve meeting the convexity 

 of tb ^ outer margin, instead of a straight .sloping inner edge as in Ajih/- 

 chophis. These two lateral moieties, however, are not so frequently found 

 separate as is the case with Aptiichoiysifi. In some instances a smaller 

 notch appears at the bottom or apex of the curved notch, sometimes with 

 a little escutcheon peculiar to it ; but this feature requires much more 

 attention. The shield is concentrically striate as in Aptychipsis. 



1. relfocaris aphjcholdes, Salter, 1852, * Quax-t. Jour. Geol. Soc' vol. viii. 

 1852, p. 391, pi. 21, f. 10; this figui-e shows a specimen oblately circular, 

 and probably squeezed obliquely. 'Ann. ^lag. Xat. Hist.' 1860, I. c. 



