80 Mr. A. Willey. On the [May 22, 



the albumoses, but much more rapidly and severely. The animal 

 becomes ill directly after the injection, gradually becomes more and 

 more sluggish, and dies in coma, or, if a non-lethal dose be given, it 

 recovers from the state of stupor gradually. After death enormous 

 local subcutaneous oedema is found, with congestion and sometimes 

 thrombosis of the small veins. Peritoneal effusion is occasionally 

 present, and the spleen is usually enlarged, dark, and congested, 

 or simply congested without being greatly enlarged. The fatal dose 

 for a mouse weighing 22 grams is between O'l and 0'15 gram, 

 death occurring in two to three hoars. 



The anthrax bacillus in digesting the alkali-albumin forms (L) 

 proto-albumose, (2) deutero-albumose, (3) an alkaloid. The alkalinity 

 of the albumoses may explain their toxic properties, being due to 

 the fact that the alkaloid is in a " nascent " condition in the albu- 

 mose molecule. The bacillus forms the alkaloid from the albumose, 

 and it is possible that the living tissues have a similar action when 

 the albumose is introduced into a living animal. 



III. " On the Development of the Atrial Chamber of Amphioxus." 

 By ARTHUR WILLEY, Student of University College, 

 London. Communicated by Professor RAY LANKESTER, 

 F.R.S. Received May 5, 1890. 



Preface. 



Last year, through the kindness of Professor Lankester, I had the 

 opportunity of spending several months May to August in Sicily, 

 collecting the embryos and larvae of Amphioxus. 



Since then I have been working continuously on the material I 

 obtained in the laboratory of University College, under the direction 

 of Professor Lankester. The period of the development, to which 

 Professor Lankester determined first of all to give attention, was 

 that before which Hatschek's well-known work stops short. He 

 proposed that I should cut sections, so as to ascertain the mode in 

 which the atrial chamber takes its origin and the subsequent history 

 of the gill-slits, viz., as to how the slits on the left side of the pharynx 

 originate. The relation of the larval to the adult mouth and the 



~ 



details of the curious process of movement of the mouth from a uni- 

 lateral to a median position were included in the scope of our 

 enquiries. 



Professor Lankester received a grant from the Government Grant 

 Committee in aid of the present investigation, and it is therefore neces- 

 sary to state that he has constantly supervised my work, and allows 



