430 HEPOiiTS ON THfi STATE OP SCIENCE. 



lutercUri-eut with the above e.xperimeuts, the old experiment ol 

 Norris, proving that tlie shape of the red blood coi'puscle is that of a 

 'myelin form,' has been repeated with the pure lipoid substances to 

 hand in the laboratory. By making 'spreads' of solutions in alcohol 

 or ether on slides, treating with water, and examining microscopically, 

 or by pouring solutions into water, shaking, and centrifugalising, all 

 varieties of myelin forms were formed from pure lecithin, commercial 

 lecithin, cholesteryl oleate, kephalin, cerebrin, and mixtures of these 

 substances. 



The biconcave-disc and the cup forms of red blood corpuscles are best 

 got by using a mixture of 2 per cent, lecithin and 1 per cent, cholesteryl 

 oleate in alcohol, either poured into water or dried on a slide and treated 

 with water. These ' artificial corpuscles ' are, especially after staining, 

 easily confouiided with real corpuscles similarly treated. 



Norris attributed rouleaux formation to the lipoid pellicle of the red 

 corpuscles, but it must be stated that the * artificial corpuscles ' prepared 

 from pure lecithin and cholesteryl oleate and mounted in water show no 

 tendency to stick together. One can watch them approach each other, 

 touch, and swim apart. 



Apparently the cholesteryl oleate, or some such body, ia necessary for 

 the formation of a good imitation of the natural shape. 



Lecithin alone, cholesteryl oleate alone, or lecithin and crystalline chole- 

 sterine give emulsions consisting of tubular myelin forms in the first case, 

 or irregular irranular forms in the latter two. 



The addition of cerebrin to the lecithin and cholesteryl oleate interferes 

 with the formation of good imitations of the 3ha,pe of a red corpuscle. 



Peat Moss Deposits. — Interim Uepovl of the Committee, consistinc/ of 

 Professor R. J. Harvey Gibson (Chairman), Professor K. H. Yapp 

 (Secretary), Professor J. R. Green, and Mr. Clement Reid, 

 appointed to investigate the Feat Moss Beposits in the Cross Fell, 

 Caithness, and Isle of Man Districis. 



The Committee have received the following Report from Mr. Francis 

 J. Lewis : — 



This investigation has so far been confined to the Cross Fell District. 

 Owing to the complications met with in the peat strata much section 

 cutting has been necessary. These complications are due to two causes : 

 (a) the variation in altitude from 2,850 to 1,400 feet ; (i) to widespread 

 beds of silt and clay intercalated in the peat. 



The silt has been brought down from Cross Fell lying at about 2,500 

 feet at certain intervals and spread broadcast over the lower ground. 

 This has introduced local changes in the flora, due to ecological factors, 

 and has made the correlation of the various beds extremely difficult. 

 The lower ground, lying at 1,800 to 1,500 feet, has still to be examined, 

 and it is hoped that here better evidence will be obtained as to the posi- 

 tions of the lower and upper forest beds. 



The chief point of interest up to the present time is the discovery of 

 a well-marked arctic-plant bed lying at the base of the peat. A silty 



