I 



Bibliographical Notices. 379 



oblivion, or transferring the name of one species to another until 

 it ceases to have any definite meaning. 



But apart from those faults and inaccuracies it is impossible to 

 overestimate the value of such a Catalogue, dry enough, it is true, 

 to a non-scientific reader, but to the ornithologist working with the 

 birds in this magnificent collection truly a " friend in need/' 



Over den bouw der Schelpen van Brachiopodcn en Chitonen. (On the 

 Structure of the Shells of Brachiopods and Chitons.) Doctor- 

 Dissertation. Leiden, 1882. By Dr. J. E. Van Bemheli^. 



In this work the author gives a chronological list of the literature 

 relating to the anatomical structure of Brachiopods ; a short account 

 of the contents of the most important works, especially with a view 

 to the different opinions entertained with respect to the affinities 

 and homologies of Brachiopods ; an historical review of the investi- 

 gations of others on the structure of their shells; and, finally, some 

 observations of the author's on this subject, illustrated by a few 

 figures, showing the different aspect presented by the under surface 

 of the shell in different parts, and a transverse section through a 

 tubular mantle-papilla. 



The chief part of these contents, translated into German, are to 

 be found in " Untersuchungen iiber den anatomischen und histolo- 

 gischen Bauder Brachiopoda Testicardinia " in the ' Jenaische Zeit- 

 schriftfiir Naturwissenschaft,' Bd. xvi. neue Eolge, Bd. ix. Heft 

 1 & 2, 1883. 



As 



with 



pods ; especially the opinions of Steenstrup, Huxley, Hancock, Morse, 

 and the Hertwigs are noticed, and, finally, Biitschli *s supposition 

 that the Chsotognathi are perhaps the nearest allied to Brachiopods, 

 on account of their development, is mentioned. 



The structure of the shell was investigated by making transverse 

 sections through decalcified fragments. Xo communication between 



csecal cavities in the mantle-tubules and lacunae or vessels in the 

 mantle itself was found. The corpuscles in these tubules seemed 

 to be for the greater part nuclei belonging to cells that clothe the 

 walls of the shell-perforations. No openings in the periostraeum. 

 occurred on the tops of the caeca, which tops showed with perfect 

 clearness the radiating ring of fine striations discovered by Car- 

 penter and King. 



The number of cseea on the same part of the shell-surface in very 



old and very young specimens of Waldhei ia crm >u,i was found 

 to be the same'. This fact shows that the distance between two 

 caeca does not chan > with age, and led the author to the conclusion 

 that no intussusception v ars daring the growth of the shell. 



The bases of the calcareous prisms were found to be very regu- 

 larly shaped at the margin of the shell, but (especially in Terebra- 

 tifla and TerebmtoAim septentrionalis) they became very irregular 



26* 



