BEAUTIFUL DISSECTIONS. 1 4 1 



site which infests the nervous system of the haddock 

 and the cod, but as his views on the structure of this 

 animal appear in vol. ii. p. 497, it is unnecessary 

 to dwell upon them here. In his account of the 

 Trichina spiralis, he states that from the winter of 

 1843 to the date of his lecture in 1847, no subject 

 infested by this parasite had been received into the 

 anatomical rooms of the University, curiously con- 

 trasting with the frequency noticed of late years in 

 Germany. 



In his lectures on the annelids, insects, and Crus- 

 tacea, he argued that the dorsal vessel of these animals 

 is homologous not with the aortic trunk of the Verte- 

 brata lying beneath the spine, but with the heart and 

 primitive aorta. 



His lectures on the tunicated molluscs were illus- 

 trated by many beautiful dissections, some of which 

 had been exhibited to the Wernerian Society in January 

 1841. As the tunic of Phallusia vulgaris possessed 

 so many vessels, it was found, on injection, to assume a 

 bright vermilion tint. He had succeeded in injecting 

 both the vein and artery which enter the outer tunic 

 of the animal, and had recognised a free and frequent 

 anastomosis in its substance. Where this outer tunic 

 w;is adherent to any object, it gave off, as it were, nu- 

 merous processes or prolongations, which projected from 

 the genera] surface, and in these the ramifications and 

 anastomoses of the blood-vessels were most numerous. 

 Eence this tunic was to be regarded as something more 

 than a mere cuticle. 



