us with an extensive series of figures and descriptions. And 

 although, as he himself properly remarks*, " some respectable 

 writers have amused themselves with either giving them new 

 names or arranging them as Spongice, Alcyonia" &c., those 

 writers have assuredly done nothing more ; and thereby, instead 

 of advancing the knowledge of these fossils, they have introduced 

 all the confusion and uncertainty which it has been possible to 

 do as to even their identity. 



Dr. Johnston, in his ' British Zoophytes' (2nd ed. 1847, p. 180), 

 merely takes a passing notice of the Ventriculidse ; but his work 

 does not profess to include fossil species. 



Finally, Mr. Morris, whose wand has in many instances re- 

 stored order where numberless writers had " amused themselves 

 with giving new names/' while he properly readmits the Ventri- 

 culidse to their position as a separate genus, has placed them 

 among the Amorphozoa. It is needless to dwell on the impro- 

 priety of that position, as Mr. Morris is now fully satisfied, from 

 an inspection of my collection, that they deserve a very different 

 place. And if constancy and elegance of form, delicacy of struc- 

 ture, and a high state of organization are to be taken as tests, 

 the Ventriculidse will assuredly have hereafter to be ranged in a 

 very different group from that of the Amorphozoa. 



Having thus shown what has been already done in the field 

 upon which I have entered, it is necessaiy, in order that the 

 reader may have any confidence in the results and observations 

 which will be presented to his notice here, to state the course 

 which I have myself pursued in these investigations. 



The first specimen of the Ventriculidse which came under my 

 notice strongly attracted my attention from its great elegance of 

 form and the peculiarities I observed in it. I was disappointed 

 in finding any satisfactory information on its nature, and soon 

 perceived that every one of the characters described in the books 

 had reference to some superficial characters only, and not to the 

 intimate structure of the animal. Being fully satisfied that " it 

 is only by a strict investigation of the intimate structure of the 

 various forms of these animals/' as an accurate observer has well 

 remarked f, "that any permanent arrangement that shall indi- 

 cate their true and natural affinities may be hoped for," I set 

 about that task myself : this has now engaged my attention for 

 upwards of two years ; and in now publishing the results of my 

 careful observations, I feel that I may add with even more truth 

 than could be done by that writer, that the task I have under- 

 taken " is a task of no little difficulty in the accomplishment, 



* Geology S.-E. England, p. 97. 



f Farre on the Ciliobrachiata, Phil. Trans. 1837, p. 387. 



