Dec, 9, 1875] 



NA TURE 



107 



' late friend. It is of course impossible to supply the place of the 

 ' naturalist whose collections I shall do the best to describe, for 

 I with him has perished much knowledge of the habits and distribu- 

 tion of the animals, and although this want can be partially atoned 

 for by the copious notes he has left behind, much unfortunately 

 , can never be replaced. . . . There is always more difficulty in 

 procuring specimens of Mammalia than in collecting terrestrial 

 animals belonging to most of the other classes of vercebrata and 

 invertebrata, and this is especially the case with the larger forms. 

 It is consequently not to be expected that the species repre- 

 sented will be more than a portion of those inhabiting the 

 country. Still the collection is rich in some respects, and espe- 

 : cially in kinds of rodents, and it adds largely to our knowledge 

 of the fauna of Western Tibet and Eastern Turkistan. The 

 ( larger mammals^ indeed, were originally better represented, but 

 \ after Dr. Stoliczka's death many specimens appear to have been 

 \ remci-ed from the collection. Such at least was the case with the 

 i ruminants. In a private letter which Dr. Stoliczka wrote to 

 me, he told me he had sent twenty-two skins of wild sheep from 

 1 Kashgar. Of these only eleven — seven males and four females — 

 i are now forthcoming, and not one of these has fine horns. There 

 ; is not a single specimen of Ovis poll from the Pamir, the original 

 locality, although I have reason to believe that Dr. Stoliczka 

 ' brought away one head at least. Lastly, there are skeletons of 

 ild sheep and ibex in the collection of which the heads have dis- 

 f>eared. It is highly probable that other specimens besides 

 ise of Ovis poll have been similarly made over to priva'ie 

 ividuals. The value of the collection has been seriously 

 minished by its being broken up, ,and the finest specimens 

 I distributed, before it had been examined," &c. 

 ' (True extract.) H. H. GodwinAustev, 



Superintendent Topographical Survey of India 



Glands of the Cherry Laurel 



Is Nature (vol viii., p. 245) Mr. Thiselton Dyer, in answer 



I to a correspondent, says that he knows of no explanation ot the 



purpose or origin of the nectariferous glands on the back of the 



af of the cherry laurel. Mr. Darwin ("Origin of Species," 



ah edition, p. 73) says: "Certain plants excrete sweet juice, 



,appar<;ntly for the sake of eliminating something injurious from 



the §ap ; this is effected, for instance, by glands at the base of 



khe stipules in some Leguminosa;, and at the backs of the leaves 



lof the common laurel. This juice, though small in quantity, is 



igreedily sought by insects ; but their visits do not in any way 



benefit the plant." Glands cannot be considered very complex 



imodifications of cellular tissue. They exist on all parts of plants, 



;and contain a great variety of secretions. Mr. Darwin and others 



ihave shown that they perform the varied functions of secreting 



■nectar to attract insects to flowers, of secreting odorous matter 



for the same purpose, of absorbing ammonia from rain-water and 



the products of decomposed or digested animal or vegetable 



alter, and of secreting acids capable of digesting solids. The 



dstence of free acids in the plant would be injurious to it, so 



at their excretion would be beneficial to it apart from any 



:gestive function which they may in some cases perform. The 



ands of the laurel are so far unspecialised that they are by no 



eans constant in number or size. As their attracting insects is 



: no service to the plant, the nectar must be said to be 



xcreted ; but, being what Sachs has termed (p. 629) a "secon- 



iry product ot metastasis," it should be looked upon rather as 



physiologically accidental excretion than as positively injurious, 



^ a substance which, having ceased to take part in the processes 



" growth, has not acquired an indirect function as has the nectar 



f flowers. To account for the position of the glands it may be 



aggested that, as in other evergreens, the leaves of the laurel 



re " reservoirs of reserve material " in which metastasis, in- 



uding the separation of the "formative materials " from the 



secondary products," mainly takes place (Sachs, p. 627). 



G. S. BOULGER 



8, Westbury Road, Harrow Road, \V. 



Saw-fish inhabiting Fresh Water 

 I AM not aware if a curious fact connected with the lake near 

 ■lanila has been noticed by any traveller. 



The Laguna de Baij is a large sheet of water some ninety miles 

 n cifcumference, divided by an island and two peninsulas, from 

 vhich it is often spoken of as the "lakes." This lagoon receives 

 he waters of the small rivers of the provinces of the Lagima 

 ud Morong, and its only outlet is the river Pasig, which flows 



into the bay between the military city and suburbs of Manila. 

 The volume of water discharged by the Pasig is augmented by 

 that of another river which joins the main stream some eight or 

 nine miles from Manila, and during gales in the S. W. monsoon, 

 which prevent the free egress of the water, the Pasig overflows 

 and covers the flat land round Manila. 



The water of the lake is quite fresh, and after settling, perfectly 

 potable. At certain times the waters of the lake of Baij possess 

 an urticating property which makes bathing very disagreeable 

 from the irritation they produce. The natives (who account for 

 everything in some way or other) attribute this to the Pistia, a 

 plant which is so abundant as to fill up small bays and form 

 floating islands of considerable size. Great quantities of this 

 plant are carried down the river into the bay, and are seen some- 

 times a lon^ way oat at sea, killed and yellow Irom the effect of 

 the salt water. Sections of the leaves are beautiful microscopic 

 objects. Tne lake is separated from the Biy of Manila by a few 

 miles of very flat land, and there can be little doubt that before 

 this barrier was thrown up it formed part of, or at least com- 

 municated with, the bay. One proof that the waters w^re once 

 salt is the existence of a bank of fossil oysters at the point of 

 Julu-julu, some twency miles from the outlet by the river. 

 When this barrier was raised the waters of the lake became 

 gradually fresh from the influx of those of a number of small 

 rivers which drain the surrounding provinces, the only outlet for 

 which (as before mentioned) is the river Pasig. 



The peculiarity to which I have alluded is the existence of a 

 species of small shark and numbers of Saw-fish (Pristis) in the 

 perfectly fresh water of the lake. They are seldom or never met 

 with in the river, but there is a fishery in the lagoon in which 

 numbers of the latter are taken. The flesh is eaten, the livers 

 give a good deal of oil, and the snouts of the larger specimens 

 make very formidable %veapons, which the natives use and which 

 are at times sent down to Manila as curiosities. These saw-fish, 

 now living in perfectly fresh water, have no doub: become gra- 

 dually accustomed to the change, as has been the case with the 

 marine species of Crustacea discovered by Prof. Loven in the 

 fresh water lakes of Sweden. * 



I am unable to describe the sharks, which I think from the 

 account given me are a small species of dog-fish, quite harmless. 

 Very diff^erent, however, are a larger kind inhabiting the brackish 

 water of the lake of Bombon, in which is situated the active 

 volcano of Taal (south-east of the great lake, about twenty or 

 twenty-five miles distant by road). This kind of shark is feared 

 by the natives, who avoid bathing at points which they frequent. 



Manila W. W. W^OOD 



Observations on Fish 



In May last the writer dug a tank within the premises at 

 Garden Reach. About the end of July it was stocked with 

 young fish of several kinds, among others a species of carp, 

 called by the natives " Katlah," which abounds in the turbid 

 waters of the Hooghly, within the range of the tides. The fry 

 varied from halt an inch to an inch in length, some even smaller. 

 The " Kutlah " does not breed in fresh water, but attains an 

 extraordinary size in a wonderfully short time in ponds. So very 

 rapid has been the increase of the fish in question, that the fact 

 seems worthy ot chronicle in the pages of Nature. On Sept. 

 22, the tank was swept with nets to catch one or two fish of 

 the pike species that had been introduced accidentally with 

 the others, and attained a size that rendered them dangerous to 

 the fry of other kinds. In the net several dozens of the " carp " 

 referred to were taken ; one of the largest weighed 14 oz , and 

 measured 1 1 inches from the end of the upper lip to the tip of 

 the tail, i| inches thick behind the shoulder, and 34 inches in 

 breadth ; the others were only one or two ounces lighter. 



The tank (pond) in which these fish throve so marvellously is 

 only 65 feet long by 58 feet broad, and 13 feet deep. The 

 natives, many of whooi live within the compound, wash their 

 rice and other food in the water, preparatory to cooking, furnish- 

 ing the fish with a large amount of food. As the writer saw the 

 tank dug and the fish put m, there cannot be a doubt about their 

 increase in the short space of three months from small fry barely 

 an incn lung, to fair-sized fish 1 1 to 14 oz. in weight, measuring 

 from ID to II mches. Robert U. S. Mitchell 



Misti and its Cloud 



In N.\TURE, vol. xii. p. 487, Mr. Stevenson gives an inte- 

 resting example of the genesis of clouds, due to hills of about 

 * Sec Naturk, vol. L p, 434. 



