206 



placed at nearly equal distances, and almost in straight lines: the lines 

 of articulation preserving the same direction. This specimen, I have 

 reason to believe, is from Wenlock Edge, to which place, or rather 

 to its fossil productions, I shall soon have to recur. In another speci- 

 men, not marked with sufficient distinctness to be employed as"a sub- 

 ject for delineation, a middle state, as it were, is to be observed. The 

 minute openings, as well as the lines of articulation, are disposed 

 with much less regularity than in the specimen just described, but 

 with considerably more than in the preceding. 



In Knorr's elegant work, a fossil is depicted which is evidently of 

 the same species with those which are here figured ; the regularity with 

 which its lines of articulation and its small openings are disposed, ren- 

 dering it most like that which is represented Fig. 8. From the re- 

 marks of Mr. Walch on this fossil, we learn that it was obtained from 

 the Isle of Gothland; and that its specimens are sometimes, as is the 

 case with Fig. 6, pervaded with a tinge of red. They differ much, he 

 observes, in thickness as well as in length; some being not more than 

 half an inch, whilst others are two inches in thickness ; they vary also 

 in length from one to five or six inches. It is, however, well de- 

 serving of remark, that according to Mons. Klein's account, the 

 limeburners of Gothland often find these entrochi of the length of an 

 ell. Their central opening, Mr. Walch observes, varies as in the 

 other entrochi, being sometimes circular, and sometimes, though 

 very rarely, stellated. It is only with the assistance of a glass, he 

 observes, that the lines of connection between the trochites, as well 

 as the numerous little openings between these lines, are to be plainly 

 seen. Of these openings, he says, it is observable, that they pass 

 through the substance of the trochites, and open into the central ca- 

 nal ; and in general, he says, they do not bear any marks of having 

 given off branches; although, he observes, it is certain that some, at 

 least, do ramify ; since, in a specimen which he possesses, there is a 

 ramification, which is given off from the larger trunk, possessing similar 



