458 Prof. T. Rupert Jones — On the Palaeozoic Phyllopoda. 



a/926) without carapaces, is troublesome and unsatisfactory to deal 

 with. We find some equivalent styles and broad blade-like stylets, 

 like long scalene triangles, in G. papilio, stygia, acuminata, etc. ; but 

 none of these seem small enough for the several little sets of trifid 

 appendages, more or less perfect, which we have met with. C. robusta 

 takes in some of these ; but Oxford Mus. T is relatively broad, and 

 might be termed lata ; B.M. 58878, from Muirkirk, has very narrow 

 members (angusta) ; and one set in the Owens College is so neat, 

 symmetrical, and small that it might be called minuta. 



11. The specimens Ludlow Mus. S. and M.P.G. X-fV 2 have each 

 a long style and a strong stylet attached to a broken ultimate 

 segment, and were regarded as var. longa in the Third Eeport, 

 p. 25. Although not showing the lattice-pattern so often seen on 

 the segments of C. papilio and C. stygia, they may well belong to one 

 of those species, and the ornament may have flaked off from the 

 ultimate segment. The study of C. papilio and stygia (Third 

 Eeport, pp. 16-20) we have not yet exhausted by any means. We 

 know, however, that the abdominal segments were delicately sculp- 

 tured with leaf-like or lattice-pattern ornament, the points of the 

 triangles pointing upwards, or rather backwards, towards the cara- 

 pace, and one limb of the triangle, where free, running downwards 

 and outwards in the other direction. These oblique lines are often 

 visible when the triangles have disappeared from wear or decom- 

 position. Among many others the segments M.P.G. X iV 1 ; B.M. 

 41900 ; Oxford Mus. A and H exhibit fine examples of this leaf-like 

 ornament ; and it is visible in several more complete individuals in 

 those collections. In the Braidwood and Glasgow Museums numer- 

 ous specimens show it well. See also Third Eeport, p. 31. 



12. A small and very delicate specimen, B.M. 59648, has a thin 

 subovate carapace, with excessively fine parallel longitudinal stride, 

 and shows 14 or 15 segments, some within and five outside the 

 carapace, ending with a neat trifid set of appendages. This differs 

 from any other form we know ; and probably some small loose 

 bodies, of numerous segments, occurring in the Lesmahago shales 

 (Third Eeport, p. 20) may be of the same species. Its looseness 

 of structure would suggest the name laxa. 



13. Of C. Salteriana, noticed as a new species in the Third 

 Eeport, p. 23, we have not yet seen any additional specimens. 



14. The specimens which we referred to in the Third Eeport 

 pp. 23 and 24, as C. cassia, Salter, are separable into two forms. 

 C. cassia proper is recognized on an interesting slab, of which one 

 counterpart is in the Ludlow Museum (E and F) and the other 

 in the Museum of Practical Geology at Jermyn Street, London (X-r). 

 The other, somewhat similar, but larger and otherwise different, 

 specimens are not unlike in the characters of the carapace, but they 

 have more abdominal segments exposed and proportionally longer 

 caudal appendages— M.P.G. X- 2 V; B.M. 39400; Ludlow Mus. K ; 

 Oxford Museum L and Q. These might be conveniently named 

 C. cassioides. 



In all the specimens of both kinds the carapace has been ap- 



