176 



THE TROPICAL AGRICULTURIST. 



[August i, 1882. 



I -will now quote from letters reoehed from oue of 

 my coiTesiiLOiilunts in Ceylon, a gentlemau of great ex- 

 perience anil knowled'je in seiiciciiltiu'e. 



In a letter, dated 24th August, 1881, my correspondent 

 says: — "The Athm moth seems to be a near relation 

 of the Cyiitliia, and woiUd probably feed on the AUanthus. 

 Here it feeds on the ciuuamou aud a gi'eat number 

 of other trees of widely different species ; hut the tree 

 on which ,1 have kept it most successfully in a domestic 

 state is the Miliiea Jto.vburghiuiia, a handsome tree, 

 mth dark-greou ternate leaves, which keep fresh long 

 atfer being detached from the tree. I do not think 

 the cocoou can ever be reeled, as the thread usuaUy 

 breaks when it comes to the opeu end. I have tried 

 to reel a gi'eat many Atlas cocoons, but always found 

 the process too" tedious and troublesome for practical use. 



"The Mylitta (Tusser) is a more hardy species than 

 the Atlas, and I have had no difficidty in domesticating 

 it. Here it feeds on the cashe\s'-nut tree, on the so-called 

 ahuond of this country [Turiiuualia catappa), wliich is a 

 lirge tree entirely diS'erent from the Em-opean almond, 

 and on many other trees. Most of the trees whose 

 leaves tm-n red when about to fall seem to suit it, but 

 it is not confined to these. In the case of the Atlas 

 moth, I discovered oue thing which may be well worth 

 knowing, aud that was, that with cocoons brought to 

 the seaside after the larvfe had beeu reared iu the Central 

 Provinces, in a temperature ten or twelve degi'ees colder, 

 the moths emerged in from ten to tiveuty days after the 

 formation of the cocoon. The dm'ation of the j>upa 

 stage in this, and probably in other species, therefore, 

 depends upon the temperatm'e iu which the larvae have 

 lived, as well as the degree of heat iu which the cocoons 

 are kept; aud in transporting cocoons from India to 

 Europe, I think it wiU be found that the moths are 

 less liable to be prematm-ely forced out by the heat of 

 the Eed Sea when the larvse have been reared in a wai-m 

 climate than when they have been reared iu a cold one. 



"I do not agree with the opinion expressed in one 

 of yoru' reports, that the short dm'ation of the larva 

 stage, caused by a high temperature, has the efl'ect of 

 diminishing the size of the cocoons, because the Atlas 

 and Tusser cocoons proluced at the sea-level here are 

 quite as large as those found in the Central Provinces 

 at elevations of 3,000 feet or more. According to the 

 treatise on the "Silk Manufactiu'e," iu "Lardner's Cyclo- 

 pfedia," the Chinese are of opinon that one di'achm of 

 mulberi-y silkworms' eggs ^Hl produce 25 ounces of 

 sillc if the caterpillars attain matiu'ity within 25 days ; 

 20 ounces if the commencement of the cocoons be delayed 

 until the 28th day; and only 10 ounces if it be delayed 

 until between the 30th and 40th day. If this is correct, 

 a short-lived larva stage must, instead of causing small 

 cocoons, produce, just the contraiy effect." 



In another letter, dated Nov. 25th, 1881, my cor- 

 respondent says: — "I am son-y that you have not had 

 better success in the rearing of your larva;, but you 

 should not despaii'. It is possible that the choice of 

 an imin-oper food-plant may have as much to do with 

 failures as the coldness and dampness of the English 

 climate. I lost many thousands of Atlas caterpillars 

 before I found out the proper tree to keep them on 

 iu a domesticated state; and when I did attain partial 

 success, I could not keep them for more than oue 

 geueration, tiU I found the Milnea Buxbuniluana to 

 be their proper food plant. I do not kuow the proper 

 fool-plant of the Mylitta (Tusser), but I have succeeded 

 very well with it, as it is a more hardy species than 

 the Atlas. Though a Botnhyx be pol^^jhagous iu a state 

 of nature, yet I think most species have a tree proper 

 to themselves, on which they are more at home than 

 on any other plant. I shindd like, if you could find 

 out from some of your correspondents in India, on 

 what species of tree Myiitta cocoons are found in the 

 largest numbers, aud wliat is about the gi-eatest number 

 round on a single tree. The Mylitta is common enough 



here, but there does not seem to be any kind of tree 

 here on which the cocoons are to be found in gi'eater 

 numbers than twos aud threes; and there must be some 

 tree in India on which the cocoons ai-e to be found in 

 much greater plenty, because they could not otherwise 

 be collected iu sufficient quantity for manufacturing 

 pm'poses. The Atlas is here foimd on twenty or more 

 difi'erent kinds of trees, but a huudred or a hundred aud 

 fifty cocoons or larvie may be found on a single tree of 

 Milnea lio.thuryhiana, while they are to be found only 

 singly, or in twos and thi'ees, on any other tree that I 

 know of. The Atlas and Mylittaseeia to be respectively 

 the Indian relations of the Cyntliia and Pernyi. It is, 

 therefore, probable that the Ailanthus would be the 

 most suitable Em'opean tree for the Altas, and the oak 

 for the Mylitta." 



AttacUs Mylitta (Antheraa paphia). — I did not receive 

 a single cocoon of this species for the season 1881. 

 My stock consisted of seven cocoons, from the lot received 

 from Calcutta at the end of February, 1880. Five were 

 female, and two male cocoons, one of the latter died, 

 thus reducing the number to six. The moths emerged 

 as follows: — One female on the 21st of .June, one female 

 on the 26th, one female on the 28th, one female on 

 the 1st of July, and one male on the 3rd of August; 

 the latter emerging 34 days too late to be of any use 

 for rearing purposes. The last female moth emerged, 

 I think, aliout the end of September. These cocoons 

 had hybernated twice, as has been the case with other 

 Indian species. I had Indian cocoons which hybernated 

 even three times. — Journal of the Society of Arts. 



The Inpluence of Lime in the Gekminatiok of 

 Seeds. — Some interesting results of experiments by 

 Dr. Liebeuberg as to the influence of lime on the 

 germination of seeds, have resently beeu published 

 by that gentleman iu the Journal of the Vienna 

 Academy of Sciences. It appears that the seeds of 

 many plants require the presence of lime iu the soil 

 during the germinating process or the seedlings die 

 for the want of it. It is shown also that many other 

 piano do not fail to germinate freely and well with- 

 out the presence of lime in the soil. Dr. Liebeuberg 

 also points out that plants which fail to grow through 

 the absence of lime iu the soil do not fail in con- 

 sequence of the injurious effects of any other matters 

 that may be present, but because lime is essential 

 ti their healthy growth. — North British Agriculturist. 



The Timber of British Columei.\. — Professor 

 Dawson, of the Dominion Geolgical Survey, iu a 

 report on tlie forests of British Columbia, draws attention 

 to the vast importance of the timber supplies of the 

 Province. He states that many tirst-olass mills have 

 been established iu various parts of the country, aud 

 the total annual product is stated to be about 200,000,000 

 feet, of which 25 million feet are exported to other 

 countries, 25 million feet used at home, and 1.50 million 

 feet sent to California. He estimates that 110 million 

 acres (or two thirds of the whole Province) are covered 

 witli timber. The Douglas flr, or Oregon pine, is the 

 most valuable commercial tree. It fiejueutly e.xceeds 

 eight feet iu diameter, and rises to a height, of from 

 two to three hiuidred feet, forming great and dark 

 forests. The western hemlock and the red cedar are 

 the next most important trees of the Province, both 

 of tbein, tbe latter especially, growing to a grent 

 size. Th" impoitance of these vast reserves of timber, 

 as well as of the mineral resources of tbe Province, 

 will become more apparent as settlement extends west- 

 vpirds from Munitoba towards tbe Eoeky Mountains. 

 The construction of the Canada Pacific Railway will 

 also develop the mineral and timber resources of the 

 Province. ^Cotonies atid India. 



