5. T. ramulosa. Formed of tubes connected l>y sub-dichotomous 



ramifications. Org, Rem. vol. ii. p. 18, PI. iii. fig. 1. 

 Fossil. 



6. fascicularis.O. Fabr. Fn. Groenl. 429. 



Fossil. 



7. ramosa. Koelruter Act. Petrop. p. 374, Tab. x. fig. 3. 



Recent. 



8. pinnata. Pallas el. Zooph. p. 247, n. 151. 



Recent. 



9. penicillata. O. Fabr. Fn. Groenl. p. 429, n. 430. 



Recent. 



10. fabellaris. Ibid. p. 430, n. 431. 

 Recent. 



1 1. _ stellata. Modeer. n. Act. Stockh. 1788, n. 10, Tab.vii. fig. 1. 

 Fossil. 



12. strues. Ibid. 4. n. 1. 



Fossil. Org. Rem. vol. ii. p. 16, PI. ii. fig. 1. 



An interesting fossil is found among the diluvial sub- 

 stances of the Farringdon gravel, which has not hitherto 

 been described, and which appears to belong to this genus. 



It is formed of tubes about the size of a crow's quill, in- 

 osculating frequently at its base ; the cavities of the tubes 

 are divided by very closely-set transverse plates, pierced 

 with a small, well-defined central foramen. Further oppor- 

 tunities of examining the fragments of this fossil are ne- 

 cessary to allow of determining whether there exists any 

 other communication between the tubes besides that re- 

 sulting from their early inosculations. Until then its specific 

 characters can hardly be considered as ascertained ; but, 

 should nothing contradictory be discovered, it may be dis- 

 tinguished as T. anastomosans. 



This fossil is seldom found in a state which will lead to a 

 suspicion of its nature. The broken tubes, for they are ge- 

 nerally in fragments, have mostly a whitish and shelly ap- 

 pearance ; but, on their surface being examined with the aid 

 of a lens, it is found somewhat to resemble that of shagreen 

 skin, and to give the notion of its having been covered by 



