1878.] Mr. J. Priestley on Batrachian Lymph- Hearts. 137 



III. "Contributions to the Physiology of Batrachian Lymph- 

 Hearts." By John Priestley, Assistant-Lecturer in Physi- 

 ology in Owens College, Manchester. (From the Physio- 

 logical Laboratory of Owens College.) Communicated by 

 Professor ARTHUR Gamgee, F.R.S. Received January 31, 

 1878. 



The following paper contains a summary of observations made in 

 order to obtain data for a comparison between the blood-heart and 

 lymph-hearts of frogs. The comparison is to include the actions of 

 electrical currents and of the so-called cardiac drugs, atropia, physo- 

 stigma, muscaria, antiar, &c. ; but this paper will treat only of the 

 electrical portion of the work. 



Before proceeding to the collection of facts especially fitted for com- 

 parison, the normal anatomical and physiological arrangements of the 

 lymph-hearts were examined ; and, as the result of this examination, 

 the author is able to confirm the discoveries of previous observers in 

 the following points : — 



1. The lymph-hearts of Rana temporaria are muscular sacs, whose 

 walls consist of branched, anastomotic, transversely striated muscular 

 fibres, abundantly nucleated (Leydig,* Waldeyerf ). A cursory exami- 

 nation failed to discover any ganglionic nervous elements among the 

 muscular fibres themselves, their absence having already been noticed 

 by Volkmann]; and Waldeyer ;§ but nerve-ganglia are said to be found 

 near the hearts, in their connective tissue environment (Waldeyer). || 



2. The lymph-hearts beat with a mean rate of 60-70 a minute, and 

 are independent in their rhythm of one another, of the blood-heart, 

 and of the respiratory movements (J. Muller)^[. But the normal pul- 

 sation is not quite regular, being occasionally broken by sudden pauses 

 or by periods of increased rapidity of beat. These interruptions seem 

 to be partly due to movements of the animal, but in part to hitherto 

 undefined causes. 



3. The hearts receive nerve-fibres from the spinal cord, which de- 

 scend in the second and tenth spinal nerves respectively for the anterior 

 and posterior pairs of hearts (Yolkmann,** Eckhard,tt Schiff JJ). 



* Leydig, Lehrbuch der Histologie, 1857. 



f "Waldeyer, Henle u. Pfeufer's Zeitsch. fur rat. Med., 3rd Series, vol. xxi, 1864. 



X Yolkmann, Muller's Archiv, 1844, p. 419. 



§ Waldeyer, loc. cit. || Waldeyer, loc. cit. 



% J. Miiller, Philosophical Transactions of Hoy. Soc. London, 1833. Poggen- 

 dorff's Annalen, 1832. Muller's Archiv, 1834. 

 # * Yolkmann, loc. cit. 



ft Eckhard, Henle u. Pfeufer's Zeitsch., 1849, vol. viii. 

 It Schiff, Henle u. Pfeufer's Zeitsch., 1850, vol. ix. 



