176 



THE TROPICAL "AGRICULTURIST. [September 1, 1884. 



powder gave us the following quantities of extracts : — 



1 Kilogr. of coca, exhausted by boiliug water, gave 



305 grammes of extract. 



1 do. do. Alcohol at 21 deg. gave 



365 grammes of extract. 



Alcohol at 56 deg. gave 



35G grammes of extract. 



do. do. Alcohol at 95 deg. gave 



210 grammes of extract. 



Sulphuric ether gave 



19t> grammes of extract. 



The extract obtained from boiling-water contains only 



gummy mucilage. 



The extract obtained from alcohol at 95°, as well as 

 that obtained by sulphuric ether, contains the azotized 

 fatty principles, resin, chlorophyle, tannin and the 

 alkaloid of the leaf. 



The extract obtained by alcohol at 21° and at 5G° 

 contains all tbe gummy and resinous principles of 

 the coca leaf, as well as the fatty azotized principles, 

 tannin, the alkaloid and chlorophyle. It is this 

 extract which best represents' the exact proportions of 

 the constituent principles of coca. The wiue of coca 

 at 21° and the elixir at 33° are therefore the most 

 powerful preparations. 



Alkaloids of Coca. 



Cocaink (C32H40AZ2 06). — lu 1850 M. Niemann 

 drew from the leaves of coca a new alkaloid, to which 

 he gave the name of cocaine, the formula of which 

 we have just given. 



A kilogramme of coca leaves gives about two grammes 

 of cocaine. This alkaloid is very bitter and produces 

 a marked numbness in the tongue when placed in 

 contact with that organ. It is of a yellowish white 

 and appears under the form of silky prisms. It is 

 almost insoluble in water, pi etty soluble in alcoholized 

 water, very soluble in alcohol and in ether. 



Cocaine has a strongly alkaline smell ; it neutralizes 

 acids completely and forms with them, salts entirely 

 erystallizable, 



Ecuonine. — Cocaine heated to 100 degrees in a sealed 

 tube with concentrated hydrochloric acid divides 

 itself into benzoic acid and a new base for which 

 M. Wcehler has proposed the name of ecgonine, de- 

 rived from the Greek. Ecgouine crystalizes in rhom- 

 boidal oblicpie prisms, without ami 11, sparkling and 

 enclosing a molecule of crystallized water. Very 

 soluble in water, this ecgonine is but slightly soluble 

 in pure alcohol anil quite insoluble in ether. 



Hygkine. — Hygrine, from the Greek hugros wet, is a 

 liquid alkaloid which M. Wcehler discovered while 

 treating coca leaves with amylic alcohol. The smell of 

 it reminds one of trymethiamine ; it has a strong 

 alkaline re-action, and the taste of it is not bitter; 

 its hydro-chlorate i» erystallizable, but it is deli- 

 quescent. With the bichloride of platinum it forms 

 a flaky precipitate. 



At the end of the pamphlet are given the various 

 preparations of the leaf which the author offers to 

 the public, such as, Pate (paste) Mariaui tonique and 

 pectoral ; syrop de coca ; infusions ; alcoholic tincture ; 

 pills ; hydro-alcoholic tincture or extract for the 

 immediate preparation of coca wine ; and lastly powder. 



The amount of sugar produced in the Burdekiu district 

 during this year is expected to be about 7,500 tons. — 

 Queenslatnder. 



Messes. Powers & Weightman, the well-known 

 quinine manufacturers of Philadelphia, U. S., have 

 announced that they have made arrangements with t!ie 

 Fabriea Lombards, at Milan, to manufacture quinine 

 at those works during the rebuilding of their o»n 

 factory in Philadelphia. Dr. John H. Weightman has 

 arrived in Europe to superintend the manufacture. — 

 Chemist and Druggist. 



( CACAO PESTS, TEA IN HAPUTALE, ET HOG 

 GENUS OMNE. 

 We lately received from a correspondent the follow- 

 ing letter : — 



" I send by today's tappal in a box some cacao leaves 

 on the underside of which are small insects which I 

 imagine to be Helopeltis Autonii in an early stage of their 

 growth. I showed some of them to three other gentle- 

 men who have already given their view on the subject 

 in the local papers, and have studied the iusect in all 

 stages of its growth, and they decide that it is not Dr. 

 Trimeu's Helopeltis. Not satisfied with their decision I 

 send you these and would be glad if you could get some- 

 body to indentify them, as their habits and effects on the 

 leaves are so similar to the tea bug as described by Van 

 Gorkom and other scientists. ,One of the gentlemen I 

 shewed them to promised at my request to send some 

 to Dr. Trimen three days ago, so I suppose we shall soon 

 get his decision." 



The box, containing the cacao leaves,* came to hand 

 safely, so we sent it on to our usual leferee, who 

 kindly replied as follows : — 



" Thripa (in tbe immature and perfect states) described 

 in ' Garden Pests ' page C3. They are very injurious 

 when present in large number. The remedies mentioned 

 in the ' Carden Pests ' would be difficult of application 

 on a large and extensive scale. I have seen the pest on 

 cinchona leaves sent from Nuwara Eliya." 



The insects certainly were numerous enough on 

 the leaves sent to us, but, as far as we could see, 

 the leaves were in no way injured by them. The 

 following is something of what is said about them 

 in "Garden Pests": — 



Thripa adonidum. The troublesome little insects known 

 as Tnrips, comprise a small order named Thysanoptera 

 (tassel-winged). They are minute insects seldom exceeding 

 a line in length : they have the power of springing a 

 great distance. We have found that these, like Red 

 Spider, are best held in check by the free use of the 

 syringe and clean wate>-, and that the same general con- 

 ditions favourable to F.ed Spider are also favourable to 

 Tnrips. Where they obtain a firm hold on the plants, 

 much difficulty is found in getting lid of tbem. 



The various remedies suggested are liquid insecticides, 

 fumigation with tobacco, tobacco or anuff powder, 

 sulphur and clay on hot bricks, sulphur dusted, 

 white hellebore and hot baths ! 



We have just heard that coffee in Badulla is per- 

 fectly biown with " red spider " at present, but our in- 

 formant also tells us that usually the trees most af- 

 fected bear the largest crops, as the pests seem to 

 have the same effect as drought upon the plants. 

 We are sorry to learn that Helopeltis is doing great 

 havoc among the cinchonas over in the principality. 

 This is what is said in "Garden Pests" on red 

 spider : — 



Acarus Telarius. This is a minute mite, belonging to 

 the family of spiders, Holetra. It is of microscopic size, 

 and is just seen with the naked eye as a red moving 

 speck. The genus to which it belongs {Alarm) contains 

 an enormous number of species, mostly parasitic in their 

 habits, either upon plants or animals. The present species 

 mostly begins to attack exotics when they are younir 

 and tender. The female red spider deposits its numerous 

 eggs upon the underside of leaves; they are exceedingly 

 small, whitish, and scattered over the leaves. The larva-, 

 as hatched, resemble their parents, save in size ; when 

 mature, they are of a dark-brown colour and slightly 

 hairy. Like spiders ami mites in general, they moult 

 several times before reaching maturity. They spin for 

 themselves silken webs, which shelter them from the 

 weather and other influences. The cause of red spider 

 is a dry, arid atmosphere, and to keep these pests 



