SCIENCE-GOSSIP. 



287 



My attention, however, was devoted to a continued 

 search for the hen-harrier and the short-eared owl, 

 both of which species were reported to be fairly 

 common around Kirkwall. With regard to the 

 barrier 1 found every man's hand raised against it, 

 and I wondered how it continued to survive at all. 

 I had several places noted as haunts of the species, 

 but I failed to find the bird in any of them. In a 

 different district, however, I fell in with the species 

 somewhat commonly, as I hope to notice in a 

 following paper. 



With regard to the short-eared owl, I found it 

 as common on the east side of the island as on the 

 west, and judging from the skulking nature of the 

 bird, I had reason to believe that it was much 

 commoner than it even appeared. Though it gave 

 few opportunities for the study of its habits, it 

 now and again rose without the necessity of a 

 disturber being present. On one occasion, during 

 mist, a bird rose within a comparatively short 

 distance of me and began to hunt. At no great 



height from the ground it beat carefully along with 

 wide sweep of its long wings, and its short thick- 

 set neck ever conspicuous as it gazed earthwards. 

 For a second or two it halted motionless with its 

 wings upturned through a third of a right-angle, 

 and, having proved the heather and rushes beneath 

 to be tenantless, it beat on again. In a brief space 

 it renewed its hovering, and after repeated advances 

 and many halts it dropped at last to the earth, but 

 rose again, without any prey, to resume its hunt, 

 and finally dropped behind a mound. Here it 

 remained sufficiently long to lead me to infer that 

 it had caught and devoured something, but later 

 on it rose to renew its hunting. 



The short-eared owl, during the opportunities I 

 had of observing it, was a very silent species ; only 

 once did I hear one cry, and on that occasion the 

 bird seemed to be joining his alarm with that of a 

 male harrier that had been calling uninterruptedly 

 because of my presence. 



[To be continued.) 



THE EVOLUTION' OF THE ANIMAL CELL. 



By Joseph Smith, M.R.I. A., 

 (Continued front page 253J 



F.L.S. 



pki ITOPLASM is composed of a large number 

 of different chemical substances, and of the 

 chemical nature of the matter our present know- 

 ledge is most unsatisfactory. It must be remem- 

 bered that " protoplasm is not a chemical, but 

 a morphological conception ; it is not a single 

 chemical substance, however complex in composi- 

 .it it is a matter composed of a large number 

 of different chemical substances, which we have to 

 picture to ourselves as most minute particles 

 united together to form a wonderfully complex 

 structure"! 1 /. Another feature of the substance 

 is that it cannot be placed under changed circum- 

 stances without ceasing to be protoplasm, for the 

 properties essential for its formation and on which 

 its existence or vitality manifests itself depend on 

 a 6xed organization. Hence after the organization 

 which forms the substance has been destroyed the 

 matter no longer represents protoplasm. 



her feature which i-. of great imports! 

 the evolution of the | nic mass is that 



the bodies rc|ui ..:.<<: can only be 



produced from the parent mass, in other 

 protoplasmic bodies can only be produced from 

 ;TOtoplasrn 1 thai 



plain] 

 most be the resu!' 



i thin wonderful rafa 



• rlUSl I.': .V 



to the fact that 1' diffil till to 



I 



1 



ciate or determine the nature of the chemical 

 substances which constitute the mass, on account 

 of the continual changes which take place in its 

 functional progress, as also because of the unstable 

 condition of the elementary units, since any inter- 

 ference with them essentially materially alters 

 their constitution. Further, difficulty is experienced 

 on account of the presence of many products which 

 are considered as waste products, and not easily 

 separated from the cell contents. Amongst these 

 complex substances may be signalized " proteids," 

 which are of " especial importance as being the 

 true substances of vital processes " (-). 



In proteids carbon occurs combined with four 

 other elements — hydrogen, oxygen, nitrogen and 

 sulphur, in proportions which it has been en- 

 deavoured to express by the following form 1 il.r 

 1 , II' . N w , SO"- the chemical composition 

 of a molecule of egg albumen. 



Amongst the various kinds of proldd bodies — 

 albumen, globulins, fibrins, plastins, nucleins, etc. 

 -plaxtin alone is apparently the only one peculiar 

 to protoplasm 1 j. 



1 eld .in iin 11".' 1 ' omplex "f .ill known 



bu ill now v' iy lini' has boi n dutei 



mined ■ to 'i".i chei 1 itructure. This complox Btrue 



pood in tl" in 1 plscc. upon thi vory renuirkubli 



'.1 ' .-I i".j. 1 1,1 ' i.i, " Gi hi 1 'i' Iwoi pnolojjlu " 



'I : ... .'I.I, 'I u.ll' II i.l" , .1.1 I'm,!,, 



!' in' i ucbuiii I- in r.'ii.iin ' i" 11 h. i iin 

 I I' II ,<U I'l.Hil .. I1w.11 I/, 



I ' If pill I ll< /" II .1/1111,' <l>... 



' III BI0I1 li dot 1 M.ii/' ii " ill. 1, 



1 r." la . / .. 1...1 . "Uobor Blwo] Nucloln 1 



Pli 'in " Botanl 1 i" Z( llung, il 



