July 27, 1883.] 



SCIENCE. 



103 



THE AFFINITIES OF RICHTHOFENIA. 



Dii. W. Waagen considers the results of his receut 

 study of the new genus Uichthofenia Kays. (Anemia 

 Lawrenciana Koninck) so remarkable as to deserve 

 a preliminary notice (Rec. yeol. surv. India, xvi. I). 

 Mr. Barraiide and Professors Val^rin ami Moller 

 were of opinion that this fossil was more nearly re- 

 lated to the corals than to any other class of animals, 

 while Professors Zittel and Lindstroni seemed to be 

 in favor of the view that it was a brachiopod. In 

 favor of the latter view, the microscopic structure of 

 the shell is the most important point. Its silky 

 lustre is identical with that of Productus, though 

 this seems to be effected by different means. In the 

 shell of Productus it is caused by obliquely ascending 

 prisms, whilst in Eichthofenia it depends apparently 

 on the fine lamination of the shell, as in Placuna or 

 similar genera. Of great importance is the prismatic 

 structure of the single laminae of which the shell 

 of Richthofenia is composed. Such a prismatic 

 structure is chiefly characteristic of mollusks and 

 molluscoids. Dr. Waagen has never yet observed 

 this structure in corals. In Calceola sandalina, 

 which seems the most kindred form among corals, a 

 microscopic section through the larger valve showed 

 well its radial septa ; but all these septa exhibited a 

 granular, not a prismatic structure. The punctation 

 of the shell is very similar to that of Productus, and 

 so are the hollow root-like tubes which penetrate the 

 shell-substance of the larger valve, and adhere to other 

 bodies. The smaller valve can also be very well 

 compared to the same valve of Productus, although 

 it is doubtful whether the thick parallel ridges on 

 the hinge-line of this valve of Richthofenia can at all 

 be compared to a cardinal process, and whether the 

 impressions on the valve can be taken as muscular 

 impressions. Keniform bodies are most certainly 

 absent. Nevertheless, among the brachiopods, the 

 Productides are the only ones to which the genus 

 Kiclithofenia might stand in any relation. 



Richthofenia possesses certain points of resem- 

 blance with rugose corals, — the irregular parti- 

 tions in the lower part of the larger valve ; the 

 columella-like portion, which is divided off by three 

 vertical septa ; these septa themselves, which can 

 well be compared to the primary and the two lateral 

 septa of a rugose coral ; the cellular structure of the 

 shell ; the septa-like ridges on the outer wall of 

 the animal chamt)ers, which are in connection with 

 the hollow canals which pierce the substance of the 

 shell ; and the tortuous tubes themselves, into which 

 the canals are prolonged on the outer side of the 

 larger valve. There can be no doubt, that on first 

 inspection, ignoring the silky lustre of the shell, one 

 would be far more likely to regard this fossil as a 

 coral than as a brachiopod. 



The points of similarity between Richthofenia and 

 the Rudlsta, chiefly Uippurites, are not very numer- 

 ous. If we make a .section of Kiclithofenia from the 

 hinge-line to the opposite wall, so as just to touch 

 the median vertical septum, we obtain a figure very 

 similar to what a Hippurites shows when cut so as 

 to touch the first columellar fold. Another point of 



similarity consists in the direction of the prisms, of 

 which the substance of the shell is composed. The 

 Rudista differ from all the other groups of Pelecypoda 

 in having the prisms of the outer shell arranged ver- 

 tically ; i.e., longitudinally to the whole extension 

 of the shell. The same is the case in the median 

 shell-layer of Richthofeni.a. A third point of great 

 importance exists in the pallial impression which 

 is conunon to Richthofenia and the Uudista ; and, 

 finally, it is not quite certain that the sinuations of 

 the large valve of Richthofenia on both sides of the 

 hinge-line, which stand in so close a connection to 

 the lateral vertical septa, may not be regarded as the 

 beginning of the infoldings of the shell, so character- 

 istic of the Rudista. The distance in time between 

 Richthofenia, which comes probably from the limits 

 between the carboniferous and Permian formation.s, 

 and the Rudista, which are for the most pai t upper 

 cretaceous, is so enormous, and the absence of every 

 connecting-link .so complete, that a close affinity be- 

 tween the paleozoic and the cretaceous forms should 

 not be expected. It will therefore only be possible 

 to prove the connection between the present fossil 

 and the Rudista, when fuither members of such a 

 developmental series are discovered. 



As the case now stands, it will be most prudent, 

 in accordance with the microscopic structure of the 

 shell, to consider the fossil as something like a 

 brachiopod. As far as Dr. Waagen's opinion goes, 

 he is convinced that Richthofenia is a member of 

 a series, which, branching off somewhere from the 

 rugose corals, has reached in Kiclithofenia a brachio- 

 pod-like stage, and is going to terminate its career 

 as a Pelecypod, as one of the Rudista. But opinion 

 is nothing in science, and proofs are every thing. 

 As yet, it cannot be positively denied that Richtho- 

 fenia may be a predecessor of the Rudista. 



J. B. Maecou. 



THE GREENWICH OBSERVATORY. 



Among the leading points referred to in the report 

 of the astronomer royal, W. 11. M. Christie, F.R.S., 

 to the board of visitors of the Royal observatory, 

 Greenwich, read at the annual visitation on .June 2, 

 are the following : — 



Besides the regular subjects of observation with 

 the transit-circle, — the sun, moon, planets, and fun- 

 damental stars, — a new working-list of 2,6tX) stars, 

 comprising all those down to the sixth magnitude 

 inclusive, and not observed since 1800, has been pre- 

 pared, and was brought into use at the beginning of 

 March. The entire number of transits observed with 

 this instrument during the year was 4,188; deter- 

 minations of collimation-error, 3.54; determinations of 

 level-error. 323; number of circle-observations, 4,48.5; 

 determinations of nadir-point, 298; reflection-obser- 

 vations of stars, 484. Comet a 1882 was observed 

 seven times on the meridian, and comet b 1882, three. 

 The routine reductions of all the observations with 

 this instrument are reported in an extraordinary 

 state of forwardness. From the beginning of this 

 year, a correction of — 0".39 has been applied to the 



