APPENDIX.

115

it really belongs to this species. The caudal shield, according to all the authors quoted,has a many-jointed axis, the rings of which bear a row of protuberances in the centre, andfrom seven to eight lateral ribs, of which each also has a protuberance on the centre. Theten rings of the body, represented by Dalman next to it, appear to be smooth. Suchcaudal shields are not uncommon in a pure whitish-gray limestone found in Gothland, aspecimen of which, in my collection, contains two individuals, which, unfortunately, havethe inner surface of their shell turned upwards, and the external surface so firmly fixed inthe stone, that it is impossible to detach them. I can, however, distinctly recognize sixcentral protuberances on the axis, which is the number that Dalman describes it to have,and on each side of them, the impressions of from twenty-eight to thirty rings, whilst thecentral region is surrounded by rings where the protuberances are situated. One ringcorresponds to each protuberance, and I can count two rings between the first and thesecond protuberance, three between the second and third, two again between the third andfourth, three between the fourth and fifth, and four between the latter and the sixth, afterwhich there are still six or seven behind the last tubercle ; a greater number, however, maybe existing at the upper side, where the rings are always more distinct. I can only find eightlateral ribs in my imperfect specimens, and no traces of protuberances,* which, indeed, canprobably only be recognized on the external surface of the shell. The caudal shield ofCalymene variolaris, according to Brongniart ’s and Buckland’s figures, so perfectly correspondswith the structure above described (Parkinson’s figure, I regret to say, I no longer have inmy possession), that I do not believe I am wrong in stating the ordinary Calymenepunctata to be identical with Cal. variolaris of the last-named authors. I propose, however,to retain the name of Cal. variolaris for Murchison’s species so called, this being probablydistinct; but I shall transfer the still older name of C. punctata to the Calym. variolaris ofBrongniart, which, at an earlier period, was certainly known by that name. Not havingbeen able to examine specimens myself, I must leave the question undetermined, whetherthis Calymene punctata really belongs to a distinct genus, or is a Phacops; Calymene variolaris,in my opinion, corresponds most nearly with the genus whose name it bears, and approxi-mates very closely to those species of Phacops in which there is an undivided glabella, justas C. Blumenbachii, C. Tristani, &c., are analogous to those with a lobed glabella. Thelatter might still further be grouped according to the number and form of the lobes,as in the species of Phacops, were such subdivisions required by a large number of subgenericforms.

Trilobites Sternberyii was so named by Boeck, in the May. fur Naturvidensh, which I amnot acquainted with. (See Sternberg, Verhandl. d. vaterl. Mus. etc., 1833, 51.) CountSternberg’s figure in the work just cited (1825, Table I, Fig. 5) belongs to this species,and is briefly described at the conclusion of his treatise (p. 85.) My figures (Table III,Figs. 7, 8) agree perfectly with that given by him, and were sketched from Sternberg’splaster casts. Sternberg says of the cheeks, that they are prominent. I have only beenable to recognize impressions in the cast. The eye was broken off in Sternberg’sspecimen, but its position and size are by no means left doubtful. The whole circumferencevisible has a reflexed, rounded margin. The black limestone of the Branikberg, in which

* This is the true structure, the prominent ends of the lateral ribs look like a row of tubercles.— Edit.