86 



Guide to the Invertelrata. 



GJlLLEUT those which dwell in tubes. The former order is represented in 

 ^-'^' the collection by the Eunice from Grreenlandj and by a series of 

 iSa Table ^P^cimens from Solenhofen belonging to the genus Eunicites. 

 case 79. 



Tabte- 

 case 79. 



Fig. 146. — (A) Tubes of Ortonia conica, Nicb., growing' upon the valve of 

 Mafinesquina alternata (nat. size). (B) A single tube of the same, enlarged. 

 Ordovician. 



The British collection in Table-case 79 commences with some 

 burrows in the famous *' Basal Quartzites " of Cambrian age 

 in Sutherland, which are called Arenicolites, as it is assumed that 

 they were made by worms allied to the modern lob-worm, or 

 Arenieola. There is, however, no proof that they were not made 

 by plant roots. These are associated with some equally doubtful 



I 

 Fig. 147. — Ortonia intermedia, Nich. Devonian: Canada, a, one of the 

 tubes, enlarged ; b, another example, in which the rings are greatly 

 extended laterally, enlarged. 



forms referred to the genus SerpuUtes, of which better repre- 

 sentatives occur in the Silurian. In this series the most interesting 

 worms are some species which are generically indistinguishable 



