129 



In size wltli those of the voluntary muscles generally, pervaded by 

 the two kinds of striae, and unmixed with the muscular fibre of or- 

 ganic life. 



" It may be remarked, that however adverse the appearance of the 

 very definite, sharp, and minute transverse markings may be to the 

 views of Sir Everai'd Home in regard to the constitution of the ulti- 

 mate muscular filament, still that the larger striae are formed from the 

 lateral apposition of granules, as maintained by Professor Miiller, 

 seems to be very probable. This may often be seen in the oesopha- 

 geal fibre of the horse, and still better in the heart of this and other 

 animals. Yet the beaded arrangement cannot be detected in the 

 acute and smaller striae, and the character of these appears to me to 

 be so distinct and constant, never running by insensible gradations 

 into the larger kind, and unaflfected by any modifications of light or 

 manipulation, that it is not improbable that there is an essential dif- 

 ference between them. This view also receives support from the 

 fact, that in the heart of several animals none of the smaller trans- 

 verse marks are present, the ultimate tissue being throughout gra- 

 nular, and presenting only the larger or more indefinite kind of striae. 



" It is remarkable too that in this organ the character of the mus- 

 cular fibre is altogether peculiar, being constituted exclusively, as 

 before mentioned, without a visible intermixture of any other tissue 

 whatever. Nothing can be seen in tlie heart like the fibre described 

 in the last portion, either of the gullet of the horse or of the fallow 

 deer, or indeed similar to the muscular tissue of organic life belong- 

 ing to the membranous viscera of the abdomen ; and if the cellular 

 substance exist between the cardiac muscular fasciculi, it must be in 

 a form agreeing in some respects with the ingenious hypothesis of 

 Bordeu. 



" In the preceding observations generally the muscular fibre of 

 animal life extended further towards the stomach in the outer than 

 in the inner layer of the oesophageal muscular sheath. Thus, in the 

 Otter the striated fasciculi were abundant in the former portion to 

 within half an inch of the termination of the gullet : within an inch 

 and a half on the surface they were entirely of this kind ; while the 

 muscular fibre of organic life formed the inmost layer nearly four 

 inches anteriorly to this point. 



" In the Horse, Lynx, and Deer, the organic muscular fibre, as 

 figured and described by Dr. Baly, was remarkably distinct. In the 

 first the fillets were larger than in the others, and in the last the 

 corpuscles were not seen. In many of the other observations these 

 peculiar riband-like fibres were either less evident or not to be de- 

 tected by the most careful examination, even in that part of the gullet 

 where the striated fibre constituted but a small part of, or was alto- 

 gether absent from, the muscular sheath." 



A paper communicated by Dr. Lhotsky, and entitled " Some Re- 

 marks on Animal Tuition," was read. 



Dr. Severn exhibited a species of Balisfes, which had been cau^-ht 

 on the coast of New Zealand. 



