1848.] LONSDALE ON FOSSIL ZOOPHYTES. 59 



masses on which alone they can be justly founded, have, in most 

 cases, been altogether left unexamined*." M. de Blainville having, 

 however, adopted Manon and Trciffosf, and M. Milne-Edwards f, 

 with hesitation, the three genera, solely for fossil Amorphozoa, as 

 well as M. Roemer§ with certain modifications, and M. Geinitz||, the 

 terms Achilleum, Manon and Tragos have acquired a peculiar signi- 

 fication ; and it is a duty to ascertain, so far as is possible, what are 

 the essential structures of the bodies referred to them, and whether 

 the Atherfield sponge can be identified generically or specifically with 

 any of those fossils. It is ad\dsable to begin with Tragos. 



1. The characters of that group (Petrefact. p. 12) are dense fibres, 

 and distinct, scattered, surface-openings ; but M. Goldfuss in his 

 Addenda (p. 243, 1833) considers Tragos to be equivalent with the 

 Chenendopora of Lamouroux^; and he identifies T. acetahulum'^^ 

 with Ch. fungiformis. This generic determination is proposed by 

 M. de Blainville ff also for T. pezizoides (pi. 5. fig. 8) and 2'. patella 

 (pi. 5. fig. 10) ; and by M. Milne-Edwards :(::}: for T. radiatum (pi. 35. 

 fig. 3) and T. rugosum (pi. 35. fig. 4). Chenendopiora is stated to 

 be distinguished by a funnel-form, with pores or cellules on its 

 internal surface, characters exhibited more or less distinctly by the 

 fossils just mentioned, and by T. reticulatuni (pi. 35. fig. 5) as well 

 as by T. verrucosum (pi. 35. fig. 6). These structures are clearly in- 

 sufficient, to the extent known, to be the basis of a genus ; neverthe- 

 less they mdicate a certain, uniform, physiological property in all the 

 species enumerated, except perhaps in the body represented by fig. 1 . 

 pi. 35 ; and it is believed that those fossils should not be generically 

 united to the others described under the term Tragos. Whether 

 they are in part or wholly identifiable with Chenendopora^ no e\d- 

 dence is at present accessible. It is sufficient for this inquiry to 

 state, that the Atherfield fossil differs in every leading particular from 

 those Amorphozoa, and from Chenond. fungiformis^ so far as figures 

 or descriptions can be trusted. Of the remaining eight species, 

 Goldfuss himself refers T. capitatum, a Bensburg production, to 

 Stromatopora polymorpha, which is found in the Eifel (pp. 13, 243 

 and 215) as well as at the former locality ; T. hippocastanum he 

 says is doubtful, being founded on imperfect casts (p. 13) ; and T. 

 pisiforine (p. 12) he considers may be the young of T. stellatum 

 (p. 14, where Manon is mentioned apparently by mistake ; compare 



* Penny Cyclop, vol. xxii. p. 376, col. 1, 1842. 



t Man. d'Actinol. pp. 542, 543. 



% 2nd Ed. Lamarck, ii. pp. 576, 587, 609. 



§ Verst. Norddeutsch. Kreidegebirges, Erste Lieferung, p. 2-3, 1840, 



II Charakteristik der Petrefacten des sachsisch-bohmischen Kreidegebirges, 

 p. 96, 1839-1842. Refer also to Gaa von Sachsen, p. 132, 1843. The genera have 

 probably been adopted by many other authoiities, unknown to the compiler of 

 this notice, or inaccessible to him, as Von Hagenovv and Bronn, quoted by Roemer. 



^ Exposition Methodique, p. 77. tab. 75. fig. 9-10, 1821. 



** Petref. pp. 13, 243, pi. 5. fig. 9, and p. 95, pi. 35. fig. 1. The locality Eifel, 

 given in p. 13. is stated in p. 95 to be an error; consult also Index, p. 252. 



ft Man. d'Actinol. p. 543. 



XX 2nd Edit. Lamarck, ii. p. 611-612. 



