APPENDIX. 1 1 5 



it reall}' belongs to this species. The caudal shield, according to all the authors (juotcd, 

 has a many-jointed axis, the rings of which bear a row of protuberances in the centre, and 

 from seven to eight lateral ribs, of which each also has a protuberance on the centre. The 

 ten rings of the body, represented by Dalman next to it, appear to be smooth. Such 

 caudal shields are not uncommon in a pure whitish-gray limestone found in Gothland, a 

 specimen of which, in my collection, contains two individuals, which, unfortunately, have 

 the inner surface of their shell turned upwards, and the external surface so firmly flexed in 

 the stone, that it is impossible to detach them. I can, however, distinctly recognize six 

 central 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 the 

 central region is surrounded by rings where the protuberances are situated. One ring 

 corresponds to each protuberance, and I can count two rings between the first and the 

 second protuberance, three between the second and third, two again between the third and 

 fourth, three between the fourth and fifth, and four between the latter and the sixth, after 

 which there are still six or seven behind the last tubercle ; a greater number, however, may 

 be existing at the upper side, where the rings are always more distinct. I can only find eight 

 lateral ribs in my imperfect specimens, and no traces of protuberances,* which, indeed, can 

 probably only be recognized on the external surface of the shell. The caudal shield of 

 Calymeiie variolaris, according to Brongniart's and Buckland's figures, so perfectly corresponds 

 •with the structure above described (Parkinson's figure, I regret to say, I no longer have in 

 my possession), that I do not believe I am wrong in stating the ordinary Cali/mene 

 punctata 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 probably 

 distinct ; but I shall transfer the still older name of C. punctata to the Calym. variolaris of 

 Brongniart, which, at an earlier period, was certainly known by that name. Not having 

 been able to examine specimens myself, I must leave the question undetermined, whether 

 this Calymene punctata really belongs to a distinct genus, or is a PJiacops ; 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, just 

 as C. Bluiiienbachii, C. Triistani, &c., are analogous to those with a lobed glaliella. The 

 latter 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 subgcneric 

 forms. 



Trilohltcs Stcmbcryii was so named by Bocck, in the ^Fay. für NaturridensJ,-, which I am 

 not acquainted with. (See Sternberg, Verliandl. d. vaterl. Mus. etc., 1833, 51.) Count 

 Sternberg'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's 

 plaster casts. Sternberg says of the cheeks, that they are prominent. I have only been 

 able to recognize impressions in the cast. The eye was broken ofl" in Sternberg's 

 specimen, but its position and size are by no means left doubtful. The whole circumference 

 visible has a rcflcxed, rounded margin. The black limestone of the Branikberg, in which 



* This is tbe true structure, tlie promiueut ends of the lateral ribs look like a row of tul)ercles. — Edit. 



