Sept. 14, 1882] 



NA TURE 



477 



daughter-granules are separated by the growth itself and by 

 accident, and the division is determined by the dilaceration of 

 the threads. The young granules increase in size, and acquire 

 their normal figure. After the division, there may be found 

 upon the granules a few protoplasmatic hyalin cilia, divided in 

 groups. These cilia are the remainder of the divisional threads. 

 All these cilia spring fiom points where dark spots are seen upon 

 the surface of the living granules. The compressed granules of 

 Hartwegia, of Fern-Prothallia, of Vallisneria, and Elodea offer 

 mo.-t favourable opportunities for ascertaining the manner of 

 division. This singular process is repeated again and again, so 

 that the older granules are compressed, and a filament is formed, 

 which elongates more and more rapidly as the granules increase 

 in number. Sometimes the filament may be ramified. This 

 continued multiplication by division h;s its limits ; the proto- 

 plasmatic bearer (he matter of the granule, which carries the 

 colouring substance) changes its appearance, and contains starch- 

 granules, which soon become numerous. The whole process 

 cannot, of course, be seen in the same granule, but in some, 

 dividing granules may be observed in one stage, and in others 

 in another. In such a manner (though the process is not so 

 clear) divides the endochrome of the Bacillariacere, as I have 

 studied it, in Himantidiuni pectinate. That is the manner 

 of division certainly most common. The second mode of 

 multiplication by division is more simple. The granules are 

 divided by a constriction, and separate into single granules ; the 

 daughter-granules become detached after they have reached their 

 full form and size. No cilia or threads, only a small number 

 two to three (not six to eight) are formed by the division in the 

 isthmus between the half- granules. This division is a reduced 

 form of the former, that is, the direct division without cilia ; the 

 former is the indirect division with cilia. The direct division I 

 have studied in all higher and lower green plants in all seasons of 

 the year. The second form, the direct division, is seen especially 

 in the cells of Vaucheriaand Chara. These changes in the division 

 of chlorophyll-granules of which we speak, can only be observed 

 with a considerable magnifying power (2000-3000 Iin. mag.), 

 that is the cm-e why Mikosch agrees with the other authors men- 

 tioned in disclaiming the notion of threads of the true mode of 

 division. I ascertained the-e changes in March of the year 18S0, 

 and described them in a short notice in the Magyar .' 

 Lapok (Hungarian Journal of Botany, edited by Prof. Dr. 

 Kanitz Kolosvar (vol. iv. pp. 32-43). 



II. Prof. Pringsheim, 1 after a-certain : ng the occurrence of 

 hypochlorin in all higher chl irophyll his plants, and in many 

 green algre, speaks in his paper, with reference to the Bacilla- 

 riacere, "Sie fehlt (the hypochlorin) dagegen bei den nicht 

 chlorophyll grunen Gewachsen ; also bei den Phycochromaceen, 

 Diatomeen, Phreosporeen. . . . Wenig^tens konnte ich sie 

 bisherin den genannten Pflanzengruppen noch nicht sicher nach- 

 weisen und nur Spuren derselben ist es mir gegliickt, in mancfaen 

 Kntuickelungs-tadien einiger Diatomeen aufiufindm." 1 have, 

 with the u-e of diluted muriatic acid, proved the occurrence of 

 hypochlorin in all the Haciliariacere and Cyanophycere (Phycoch- 

 romacefe) investigated. The experiment succeeded best with 

 Catothrix scopidorum. The hypochlorin was seen in all these 

 plants in the typical form of brown scales or brown drops, 



SCHAARSCHMIDT GVULA 



Botanical Institute of the Royal Hungarian University, 

 Kolosvar (Hungary), August 3 



Mimicry in the "Plume Moths" 

 I have not seen in any entomological work an attempt to 

 explain the well-known peculiar character of the wings of the 

 " Plume Moths " (Ptciophori). They depart so thoroughly from 

 the rest of the Lepidoptera in having the wings cleft into .-o- 

 called feathery "plumes" (although retaining the microscopic 

 scales characteristic of their order), that we may be certain so 

 marked a type must have been evolved along definite lines and 

 for specific reasons. One species (Agdistes Burnetii) may be 

 regarded as the first stage in the differentiation of these insects ; 

 and from this species we have succes-ive modifications in the 

 number of " plumes " up to Alucita polydactyla, where the ordi- 

 nary wings are split up into no fewer than twenty-four. 



I have long thought this wing-peculiarity is dne to mimicry, 

 the objec's mimicked being the down or pappi of thistles and 

 other composite plants. The commonest of the " Plume 



■ Ueber Lichtwirkung nnd cMorophyllfunction in der Pflanze Tahrb f 

 wiss. Bot. xii., 1851. Heft iii. p. 296. 



Moths," perhaps, is the " Large White Plume" (Pterophorus 

 pintadactylus), and all entomologists are acquainted with its 

 peculiar drifting mode of flight, exactly resembling that in which a 

 thistle plume is blown by the wind. The other day 1 followed what 

 I took to be a drifting thistle-plume, for the sake of seeing what 

 species it belonged to, and found it to be a specimen of this 

 species of moth, so remarkably similar do the two objects appear 

 when in motion. If the intention of the " plume-mouV' is to 

 mimic the pappi of winged-seeds, we can understand why these 

 insects do not fold the wings to the body when at rest, but seem 

 to display them to the utmost instead. 



The fact that (according to Stainton), out of about twenty 

 species of Pterophori, the larva; of which have their food plant 

 given, no fewer than ten feed on composite plants, or plants 

 bearing 1 lumed seeds, indicate that the resemblance of the 

 winged insects to pappi must also be protective to females when 

 depositing their eggs on plants which produce clown, as well as 

 when they are flying. It would be interesting to compare the 

 different kinds of thistle and other down with the appearance 

 of the various species of "plume-moths" which thus appear to 

 mimic them. J. E. Taylor 



Ipswich Museum, September 5 



NOTE ON SOROCHE {MOUNTAIN SICKNESS) 



IN THE ANDES 

 'THE effects of diminished atmospheric pressure on the 

 •*■ human economy seem to vary so much with different 

 individuals that a few facts of personal experience may 

 be of some interest to those who have attended to the 

 subject. During a somewhat prolonged acquaintance 

 with mountain travelling, I had never felt any of the 

 symptoms described as characteristic of mountain sick- 

 ness. The only effect of raritied air that I had been able 

 to verify was that an equal amount of mechanical effect 

 produced at a great height necessitates a greater effort, 

 so that climbing or other muscular effort causes, catsris 

 paribus, more sense of fatigue. Being in Peru in the 

 month of April last, I was about to avail myself, with a 

 friend, of the opportunity afforded by the reopening for 

 traffic of the Oroya railway, and to spend a few days at 

 Chicla, the present terminus of that remarkable work. 

 The height of Chicla above the sea is 12,200 feet, and we 

 were assured by several residents in Lima that we should 

 infallibly suffer from the soroche, the local name for 

 mountain sickness in Spanish America. Not having ever 

 experienced the slightest inconvenience at heights con- 

 siderably exceeding that limit in the Alps, I treated these 

 warnings with some derision, and in truth they had passed 

 from my mind on the evening when I arrived at Chicla. 

 I may say at once that neither there nor anywhere else 

 have I experienced any of the symptoms of mountain 

 sickness by day, or while up and moving about after 

 dark. On the evening of our arrival, after a frugal supper 

 we retired to bed about eleven o'clock. Soon after falling 

 asleep, I awoke with a severe headache, which continued 

 throughout the night, allowing only a few short and 

 broken snatches of sleep, but which passed away soon 

 after I rose somewhat before sunrise. On comparing 

 notes with my friend, I found that he also had suffered 

 from headache during the night ; but as he is somewhat 

 subject to that affection, he had not attributed it to any 

 special cause, whereas with me it is most unusual. 



The following day was spent in botanising on the 

 steep slopes upon either side of the valley at Chicla, and 

 as I was quite free from any inconvenient sensation, I 

 attributed the headache of the previous night to some 

 accidental cause rather than to diminished pressure. On 

 the second night, going to bed about the same hour, I 

 again awoke with a headache more severe than that of 

 the previous night, and was altogether unable to sleep 

 for the rest of that hight. Some two or three hours after 

 midnight 1 was suddenly seized with retching of the 

 stomach, but, perhaps because my light dinner was fully 

 digested, no further effect followed. 



We had arranged for the succeeding day to ride to the 



