388 



Miscellaneous. 



put on. In the diagram (p. 387), A represents one pair of canulse, 

 both opened and closed. B shows their position at the time of crossed 

 circulation. It will be observed that each artery requires four pieces 

 of apparatus, viz. two spring forceps to stop the blood, and two 

 canulse. Thus, when the throats were brought close together, to 

 connect the arteries cross-wise, there were no less than eight separate 

 pieces at work in a deep hollow, close together, and attached to 

 delicate arteries, none of which could be permitted to twist or interfere 

 with each other. I append a reduced sketch 

 of one of the two frameworks over which, as 

 previously described, I suspended these instru- 

 ments, with attached counterpoises, and so 

 avoided all confusion. Both pair of canulse 

 and two pair of forceps are here represented ; 

 they might be so arranged ; but it is better to 

 divide the instruments, equally, between the 

 two frames. 



For removing clots from the canulse, I tried 

 a great many plans, none with as much success 

 as I could wish. I have, however, been able 

 to extract clots from the artery itself, a good 

 quarter of an inch beyond the canulae, with a 

 wire whose end had been cut with a file into a 

 delicate solid corkscrew. I washed out the 



canulse, before reconnecting, with a thin stream of water sent through 

 the quill of a small bird, which I had fastened, by help of a short 

 India-rubber tube, to my syringe. 



The wounds require careful dressing, just like those of a man. 

 The rabbits bear the operations wonderfully well, and appear to suffer 

 little or no pain when the influence of the anaesthetics happens to 

 have left them temporarily sensible. They are often quite frisky 

 when released, and sometimes look as though nothing whatever 

 unusual had happened to them, all through the time of their 

 recovery. 



MISCELLANEOUS. 



Note on the Ichthyosaurian Head. 



To the Editors of the Annals and Magazine of Natural History. 



Gentlemen, — By an oversight, in my " Note on the Ichthyo- 

 saurian Head," the frontal bone was excluded from the anterior 

 nares of Vertebrates. Exceptions should have been made in favour 

 of Monitors and the Mammata. Whether the " Hell-bender " is also 

 to be excepted might perhaps admit of discussion. 



Faithfully yours, 



H. G. Seeley. 



