of a few Brachiopoda. 255 



2. Note on the Genus Terebratulina, D } Orbigny. 



M. D'Orbigny judiciously separated such shells as T. caput 

 serpentis from Terebratula, the loop in both these genera being 

 quite distinct; but he adds (erroneously), that the shells of his 

 genus Terebratulina are unprovided with deltidium. Impressed 

 with this opinion, he places in the genus Terebratula, T. sub- 

 striata of Schloth., a shell possessing even the external appearance 

 of many species of his genus Terebratulina, but exhibiting a fine, 

 fully developed deltidium. The interior of both T. caput serpentis 

 and T. substriata are however perfectly similar, as any one may 

 be convinced by a glance at our figures : this shows how one 

 may err by resting too much importance on simple external ap- 

 pearances, or on the presence of a greater or smaller deltidium ; 

 thus leading us to separate shells which were undoubtedly inha- 

 bited by similar animals, and to class together animals evidently 

 different. The genus Terebratulina did not therefore first occur 

 in the Cretaceous period, as stated by M. D'Orbigny, but in the 

 Jurassic epoch, where the oldest type of the genus is at present 

 known. 



Plate XIII. fig. 18, 18 a. T. caput serpentis (recent). 



Plate XIII. fig. 17, 17 a- T. substriata (Schlotheim), Jurassic. 



3. Description of Three Species of Terebratula. 

 Terebratula Haimeana, Dav. 1852. PI. XIV. fig. 1, 1 a. 



Diagnosis. Shell circular, inequivalve, depressed, wider than 

 long ; valves almost equally convex, deepest near the umbo ; 

 margin straight all round ; no trace of mesial fold or sinus ; beak 

 small, recurved, and truncated by a small circular foramen nearly 

 touching the umbo ; beak-ridges well defined, leaving between 

 them and the hinge-line a narrow false area. Surface smooth, 

 w r ith a few concentric lines of growth. Length 2 inches 4 lines, 

 width 2 inches 6i lines, depth 1 inch 4 lines. 



Obs. T Haimeana is one of the largest Devonian Terebratula 

 yet discovered, and is at once easily distinguished from T. 

 Caiqua, De Verneuil, this last being nearly twice as long as wide, 

 while the width of T. Haimeana is greater than its length ; it is 

 also distinct from T. Archiaci (Vera.), which is a much more 

 compressed and elongated shell. I was so fortunate as to dis- 

 cover the species under notice in the Devonian beds of Paffrath 

 near Cologne, some years ago, where it appears to be very rare, 

 since M. de Verneuil, whose knowledge in these matters is so 

 extensive, assures me he has not observed it in any other collec- 

 tion. I have great pleasure in naming it after M. J. Haime, 

 whose researches, along with those of Prof. M. -Edwards, have 

 thrown so much light on corals, both living and fossil. 



