JtEPOBT ON ZOOLOGY. 191 



Scien. for 1828 *, which has prmcipally for its object the 

 anatomy of Cuvier's entire group of Annelides Ahranches. So 

 far as respects the HinulinidcB, he has added little to what 

 may be found in Moquin-Tandou's work on this subject ; but he 

 has thrown much vahiable light on the structure and physiology 

 of Cuvier's first family. His researches, which relate to the 

 organs of circulation, respiration, and reproduction, have been 

 made on two species of Nais and six of Lumbriciis, which he 

 commences by characterizing. The latter he does not appear to 

 be able to identify in all cases with those of Savigny. Like 

 Leon-Dufour, he considers these animals as oviparous, and 

 thinks that what Montegre took for living young were only 

 intestinal worms. Morren's work f, which was crowned by 

 the University of Ghent, was published in 1829, and is of the 

 most elaborate nature. Taken in connexion with the researches 

 of the French naturalists, it leaves scarcely anything to be de- 

 sired as far as i*egards the anatomy and phj'^siology of the Lxim- 

 brici. Its author seems in doubt, however, about the numerous 

 species described by Savigny and others. He is more inclined 

 to regard them as simple varieties. He in some measure recon- 

 ciles the conflicting testimonies of Montegre and Leon-Dufour 

 with respect to the mode of reproduction, by asserting it to be 

 both oviparous and ovoviviparous. 



The structure of the genus Nais has been also investigated 

 by Dr. Gruithuisen. He has published two memoirs on the 

 anatomy of certain species belonging to this group in the Nova 

 Acta S)C. Nat. Cur-X. 



Before quitting this class, it may be remarked that the true 

 situation of the genus Dentalium, placed by Cuvier amongst 

 his Annelides tuhicoles, is undetermined. M. Deshayes, who 

 has made it the subject of a monograph published in the Mem. 

 de la Soc. d' Hist. Nat. de Paris§, and who has entered into much 

 detail with respect to its anatomy, seems to regard it as belong- 

 ing to the Afolhiscous type. Further researches are, however, 

 necessary in order to establish this opinion as correct. 



2. Crustacea. — Until within these few years Latreille and 

 Dr. Leach were almost the only naturalists who had studied the 

 animals of this class collectively with any degree of care or 

 minuteness of detail. The latter gentleman is well known to 

 have devoted a great deal of his attention to their arrangement 

 and natural affinities. His treatises in this department, consisting 



• torn. XV. p. 284. 



t De Lumbrici Terresiris Historia Naturali nee non Anatomia J'ractatits. 

 Bruxell. 1829. 4to. 



X torn. xi. p. 235, and torn. xiv. p. 397. § torn. ii. p. 321. 



