333 



Half way between the eye and the gills was an orifice and canal 

 leading to the mouth. The gills five in number on each side. 



The fins, and also their situation, are particularly described. 



Adjacent to the anal fins are placed two holders for the purpose of 

 grasping the female, terminated by a fiat, sharp, bony process five 

 inches long, which moves on a joint, and is, in fact, the termination 

 of a series of parts corresponding to the pelvis, femur, tibia, and foot 

 of quadrupeds. 



The pectoral fins also correspond in some measure to the anterior 

 extremities, and are connected by cartilages, which answer the same 

 purposes as the scapulae and sternum of quadrupeds. 



The heart was not larger than that of a bullock, with three valves 

 at the origin of the pulmonary artery, three at the entrance of the 

 aorta, and also two sets more, of three each, in the course of the 

 artery, at a short distance from each other. 



The stomach contained several pails full of pebbles, a quantity of 

 mucus, and a small portion of substance that looked like the spawn 

 of the oyster. 



Beside the cardiac and pyloric portions of the stomach observable 

 in other sharks, there was a globular cavity communicating with the 

 pyloric portion by a very small orifice, and by another, equally small, 

 with the intestine. 



The liver of this fish yielded about three hogsheads of oil. The 

 vessels of the liver were large enough to admit a man's arm. The 

 bile is conveyed direct to the intestine by twelve hepatic ducts, for 

 there is no gall-bladder. 



Although the Squalus here described resembles, in many respects, 

 the tribe of Sharks, it is observed to differ essentially in the form of 

 its stomach, which is intermediate between that of the shark and 

 whale. 



In the modes of generation, also, as well as in the stomachs, a 

 series of gradations may be observed from whales through the squa- 

 lus, sharks, rays, and skates, to the proper fishes ; but this inquiry 

 will form the subject of a future communication. 



Mr. Home closes the present account by such particulars as he 

 could collect concerning a large fish thrown ashore on one of the 

 Orkneys, and described as a sea-snake by those who had seen it half 

 putrid and half devoured by sea-fowl ; but it was ascertained by Mr. 

 Home to be in reality another specimen of the same Squalus as that 

 above described. 



On an Improvement in the Manner of dividing astronomical Instruments. 

 By Henry Cavendish, Esq. F.R.S. Read May 18, 1809. [Phil. 

 Trans. 1809,;?. 221.] 



The use of the common beam-compass for dividing having been 

 justly objected to, on account of the danger of bruising the divisions 

 which have been made, by replacing the points of the compass into 



