BKITISn ANNELIDS. 507 



of tlie medulla with tliose of the spiual cord is illustrated, and 

 the path is suggested (theory again) by which impressions received 

 by the trigeminus and vagus may find their way through the longi- 

 tudinal fasciculi and tractus intermedio-lateralis to the motor roots, 

 especially of those nerves concerned in respiration. 



AVe may also call particular attention to the chapters on the 

 vagus, and on the auditory nucleus. 



Among mammaEa, the observations were for the most part con- 

 fined to the sheep and the cat. A gap in comparative anatomy is 

 therefore rather indicated than filled up. 



In conclusion, we may state that the method of preparation em- 

 ployed in the investigation w^as essentially the one recommended by 

 Clarke, and that the memoir has an especial feature in being illus- 

 trated by photo -lithographs. The author has also sent us specimens 

 of the original photographs, some of which are excellent, but they 

 have all suff^ered somewhat in the process of transference to the stone. 



XLII. — Beitish Annelids. 



A Catalogtte or the Beitish Non-paeasitical "Woems, in the 

 Collection of the Beitish Museum. By George Johnston, 

 M.D., Edinb. London : printed by order of the Trustees, 1865, 

 pp. 365, 23 plates and 50 woodcuts. 



Some thirteen or fourteen years ago, it was known to many British 

 Naturalists that the late Dr. Johnston was engaged on the com- 

 pilation of a Catalogue of British Annelids, for the Trustees of 

 the British Museum. For many years previously, Pr. Johnston had 

 paid great attention to this subject, and the volumes of the " Maga^ 

 zine of Zoology and Botany," and the earlier ones of the " Annals 

 and Magazine of Natural History," contain many valuable papers 

 by him, giving descriptions of new, or little-known, genera and 

 species, while a special supplement to the later Journal, published 

 in January, 1846, was devoted to a hst of the then known British 

 Annelids, a list that, until within the last few years, when the 

 General Dredging Committee of the British Association published a 

 fuller one, was the only guide the English student had to this very 

 puzzling group. It would appear that previous to Dr. Johnston's 

 decease, the greater part of the Catalogue which we proceed to 



2 M 2 



