224 Royal Society. 



In conclusion the author conceives that he has established the 

 following propositions : — 



1st. Costal breathing may be distinguished from abdominal by 

 determining which part is first put in motion, and the kind of re- 

 spiration may be designated according to the name of such part. 



2nd. Healthy costal breathing begins with the motion of a supe- 

 rior rib, which is followed by that of the lower ones in succession. 



3rd. Ordinary respiration in men is abdominal, in women, costal ; 

 extraordinary breathing is the same in both sexes. 



4th. Any of the ribs, from the twelfth to the first, may carry on 

 respiration. 



5th. Diseased respiration is of various kinds ; the movements may 

 be symmetric or not symmetric, costal or abdominal; all or none of 

 the ribs may move ; the abdomen may or may not move ; the chest 

 may dilate in all its dimensions at one and the same time; costal and 

 abdominal breathing may alternate with one another ; costal motion 

 may be undulating or not ; and all these may be combined in one, 

 which the author terms " hesitating breathing ;" and lastly, the quan- 

 tity of air breathed is diminished when there exists pulmonary dis- 

 ease. 



" On the Structure and Development of the Liver." By C. 

 Handfield Jones, M.B., Cantab. Communicated by Sir Benjamin 

 C. Brodie, Bart., F.R.S., &c. 



The author gives a detailed description of the structure of the 

 liver in animals belonging to various classes of the animal kingdom. 

 He states that in the Bryozoon, a highly organized polype, it is clearly 

 of the follicular type ; and that in the Asterias, the function of the 

 liver is probably shared between the closed appendage of the stomach 

 and the terminal cteca of the large ramifying prolongations of the 

 digestive sac contained in the several rays. Among the Annulosa, 

 the earthworm presents an arrangement of the elements of the he- 

 patic organ, corresponding in simplicity with the general configura- 

 tion of the body, a single layer of large biliary cells being applied as 

 a kind of coating over the greater part of the intestinal canal. In 

 another member of the same class, the Leech, in which the digest- 

 ive cavity is much less simple, and presents a number of sacculi 

 on each side, these elements have a very diflferent disposition ; and 

 the secreting cells, although some remain isolated, for the most 

 part coalesce to form tubes, having a succession of dilatations 

 and constrictions, and finally uniting and opening into the intes- 

 tine. In Insects, the usual arrangement is that of long curved fila- 

 mentary tubes, which wind about the intestine ; these, in the meat 

 fly, are sacculated throughout the greater part of their course, till 

 they arrive quite close to the pylorus, where they open ; near their 

 origin they appear to consist of separate vesicles, which become 

 gradually fused together, but occasionally they are seen quite sepa- 

 rate. The basement membrane of the tubes is strongly marked, 

 and encloses a large quantity of granular matter of a yellowish tinge, 

 \rith secreting cells ; another portion of the liver consists of sepa- 

 rate cells lying in a granular blastema, which cells, in a later stage 



