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 LXXIX. Proceedings of Learned Societies, 



ROYAL SOCIETY. 



Nov. 7. J- HE meeting of this Society after the long vacation 

 was unfortunately much less cheerful than usual, in consequence 

 of the indisposision of the President, who has so long given it 

 life and vigour. A paper by Sir Evcrard Home (who was in the 

 chair) was read, relative to the comparative anatomy of the 

 Lumbricus marimis and Lumlricus terrestris, and comparing 

 their structure and habits with the Teredo navaUs. All these 

 worms have red blood ; all burrow in wood or clay ; all have 

 muscular stomachs, and their blood is aerated by tubes in their 

 • backs. The Lumlricus marinus has a small and scarcely per- 

 ceptible organ, which Sir E. considers to be a heart, near thecentre 

 of its body, where the arteries from tlie head unite, and where 

 the veins separate to supply the extremities. The author had in 

 vain endeavoured to trace their organs or describe their bron- 

 chiae, till aided by Mr. Cliff, who macerated the seaworm in 

 vinegar; this coagulated its blood, and enabled him to make 

 correct drawings of all its parts, and thereby ascertain the exact 

 point where the arteries and veins ramified. The common earth- 

 worm has an artery along its belly and a vein along its back; in 

 the latter are apertures to imbibe air. 



Nov. 14. Dr. Johnson, by the hands of the President, fur- 

 nished a paper On the Structure and Natural History of the 

 Leech of Rivulets, which he calls Hirudo vulgaris, instead of 

 Hirudo ocloculata of Linnaeus: his reason for adopting this name 

 is the circumstance tliat the Hirudo tessulala has also eight 

 eyes. The Hirudo vulgaris he describes as living under stones 

 in rivulets, being from one inch to one inch and a half, is of a 

 blackish brown on its upper side with spots and greenish under- 

 neath. It has no heart, but pulsates eight times in a minute. 

 Dr. J. thinks that the whole of the leech genus are oviparous. 

 This species copulates like snail§, is oviparous, and the ova are 

 quick in three weeks, and break the kind of capsule in which 

 they are enveloped in about two months. It deposits from six 

 to twenty or thirty ova, which are frequently destroyed by other 

 leeches. The author detailed minutely the appearances which 

 this leech affords in its various stages from the ovum till it is 

 full grown. 



Nov. 21. A paper by Dr. Philip Wilson, of Worcester, was 

 read, relating some further experiments and observations on the 

 effects of Galvanism in curing asthma. Me stated that spas- 

 modic asthma is a disease of very rare occurrence, and that Gal- 

 vanism is of no advantage to it j but that in nervous asthma in 



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