of the Chalk. 75 



the results of my own investigations to show wherein the figures 

 and descriptions in which such allusions consist have erred or 

 fallen short. 



To the paper of Guettard I have already alluded. It is suffi- 

 cient further to say, that he was not content with that mere 

 superficial glance which most later observers have given. He 

 expressly says* that, though at first he regarded these bodies as 

 related to the sponges, he was obliged to abandon that idea when 

 he had given a more careful attention to the examination of 

 them ; and he concluded that their nearest affinity was to the 

 Madrepores. 



In « Edvardi Luidii Ichnographia ' (1760), tab. 2. fig. 176, is 

 figured a Ventriculite, which he describes (p. 10) as " Astroitse 

 congener Radularia cretacea." 



Parkinson, in his ' Organic Remains of a former World ' (1807), 

 alludes to the paper of Guettard, and gives descriptions and figures 

 of several fossils which he considers as allied to Alcyonia, but 

 whose differences from which he yet felt to be marked. Plate 9. 

 (of vol. ii.) figs. 2, 6, 9 and 10; pi. 10. figs. 12, 14, 15 and 16 ; 

 and pi. 12. fig. 9 I consider to be certainly forms of Ventriculidse ; 

 and I think it probable that pi. 11. figs. 1 and 6, and pi. 12. 

 fig. 8, are so alsof. 



In Mr. Parkinson's later ' Outlines ' (8vo, 1822) he makes 

 some sound observations on the necessity for separating from 

 the Alcyonia the various bodies figured and described in his 

 former work, but he gives no additional details of importance. 



On p. 54 of the ' Outlines/ Mr. Parkinson, alluding to what 

 are undoubtedly true Ventriculidae, describes them by characters 

 which are purely external, and treats as generic characters those 

 which are merely accidental and non-essential. 



The ' Organic Remains y of Parkinson did not in the least 

 degree forestall the labours of Dr. Mantell, whose figures and 

 descriptions (1814) convey far more information on the subject 

 than all else that has even yet been published. It is but justice 

 therefore to extract at some length the description given by him 

 of these bodies. 



The generic characters assigned by Dr. Mantell, as corrected in 

 his very valuable work on ' The Fossils of the SouthDowns' (1822), 

 p. 168, are : — " Body inversely conical, concave, (1) capable of con- 

 traction and expansion : original substance spongeous ? or gela- 



* Mem. p. 259. 



f The frontispiece to the second volume, which is mentioned by Mr. Rose 

 (citation below, p. 339) as "so beautifully delineating " the structure of the 

 Ventriculite, is no Ventriculite at all, but an exceedingly different fossil in 

 all respects, viz. a Wiltshire sponge. 



6* 



