January 13, 19 16] 



NATURE 



545 



i 



The: pea^phid (Macrosiphut'n' pisi) is a weri-known ' 

 garden pest in this country and in Europe. In 1878 

 it appeared in the' United States, where it has now 

 become sufficiently important to form the subject of a 

 paper by J. J. Davis (U.S. Dept. .\gric., Bulletin 276). 

 The sp>eci€S ranges westwards beyond the Mississippi 

 illey, and is found in a few localities near the Pacific 

 cist. Among several points of interest in this bulle- 

 tin may be mentioned the fact that "oviparous females 

 may be produced by either wingless or winged fvirginl 

 females, and the same female may produce both vivi- 

 parous and sexual forms alternately." It is not sur- 

 ])rising that American syphid-flies and ladybirds prey 

 upon the aphids, as their relations do in these countries, 

 but the predaceous habits of a cecidomyid larva 

 (Aphidolctes ineridionalis), which feeds "upon the 

 juices of the plant-louse till the latter is dead," are 

 remarkable for a member of this gall-forming family. 



It is well known that during the last five years 

 numerous specimens of the handsome European 

 ground-beetle, Calosoma sycophanta, have been im- 

 ported into the New England States that they may 

 feed upon caterpillars of the gipsy moth {Porthetria 

 ■dispar), itself a species introduced from Europe into 

 North America. An account of the establishment of 

 the Calosoma across the Atlantic, recently given by 

 A. F. Burgess and C. W. Collins (U.S. Dept. Agric, 

 Bulletin 251), contains some interesting details. A 

 map shows how by natural extension and by fresh 

 importations the beetle has spread its range north, 

 south, and westwards from Boston ; "it has already 

 demonstrated that it is a very important factor in the 

 control of the gipsy moth by natural enemies." Un- 

 fortunately, the beetle is not without "natural 

 enemies" of its own in its- new home, the most 

 dangerous being that notorious Atrierican mammal, 

 the skunk, the excrement of which in some localities 

 ■consists chiefly of fragments of Calosoma. 



The widespread death and dying back of seedlings 

 ■of sal {Shorea robusta) is a very common occurrence 

 in the Indian sal forests. ; Mr. R. S. Hole, in the 

 I}idia>i Forester, vol. xli.. No. 10, gives an account 

 of his investigations into the' matter, and finds that 

 bad soil aeration and drought are the chief factors 

 responsible for the failure of sal reproduction. De- 

 ficiency of'o.xygen owing to water-logg^ing of the soil, 

 and also some toxic substanfres possibly emanating 

 from dead sal leaves, have been found to be definitely 

 injurious, since in similar soil well drained and kept 

 clear of leaves very good germination resulted. Prac- 

 tical recommendations for forest use are put forward 

 as the result of experiments made in the Dehra Duii 

 forests. 



In the Bulletin of the Department of .Agriculture, 

 Trinidad and Tobago, part v., vol. xiv., 1915, Mr. 

 J. B. Roner, mycologist to the Board of Agriculture, 

 contributes a paf>er on theAnthracnose of the mango, 

 the disease caused by the fungus Gloeosporium inangi- 

 ierae, which also attacks avocado pears, citrus trees, 

 and many other plants. \ description of the fungus 

 as it affects the flowers, leaves, and fruit of the mango 

 is given, and a plate of figures illustrirtes the appear- 

 NO. 241 1, VOL. 96] 



ance of attacked leaves and fruits. The beneficial- 

 results, of spraying the trees during the blossoming 

 period is fully described. A clean, and also a heavy, 

 crop of fruit resulted in all cases. Another noticeable 

 and valuable feature of the sprayed fruit is that it 

 keeps much longer than unsprayed fruit. This was 

 pi'oved from consignments of mangoes sent to Kcw 

 and to the United States, and also from mangoes which 

 which were kept in cold storage in Trinidad. The 

 fruit reached England in splendid condition, and a 

 number of fruits were not fully ripe at Kew twenty- 

 two days after they had been picked in Trinidad. 



The inheritance of bearding and felting in wheat 

 forms the subject of a paper by Mr. and Mrs. Howard 

 in Memoirs of the Department of Agriculture of India, 

 vol. vii.. No. 8, and is a continuation of their earlier 

 paper published in vol. v., 1912. Owing to the fact 

 that heretofore wheat with short awns as well as those 

 without beards have been described as beardless, con- 

 troversy has arisen over the results of earlier workers. 

 In the present work on Indian wheats, bearded crossed 

 by beardless — as usually described — showed two dif- 

 ferent phenomena. In one series, F-i, plants were 

 half bearded, and in the other only very short tips were 

 present on the glumes, these differences being cor- 

 related with the beardless parent; in the first place 

 the parent having tips to the glumes and in' the second 

 l>eing quite beardless. The results are set out in deFail 

 and illustrated by a very clear series of plates. The 

 inheritance of the felted character of the chaff con- 

 tinues the earlier work, but it , is shown that two 

 kinds of hairs may be present, long siHcy and much 

 shorter hairs, which are inherited separately. 



In a pamphlet entitled " The Urgfenty 'of a I>efinite 

 Forward Movement in the Study of the Active Prin- 

 ciples of South African Plants " (Capetown : Town- 

 shend, Taylor and Snashall) Dr. C. F. Juritz again 

 directs attention to the urgent necessity for a systematic 

 study of South African plants from botanical, chemical, 

 and physiological points pf viewJ' He deals with 

 several examples of toxic or medicinally active drugs, 

 and shows what progress has been made and in what 

 directions further investigation is necessary. The 

 appendix, which constitutes about one-half of the 

 pamphlet, is both interesting and valuable. In addi- 

 tion to a bibliography of the subject, it contains a list 

 of plants that so far have been examined, together 

 with the constituents that have been isolated from 

 each, and also a Jist of cases of poisoning or suspected 

 poisoning by iridlgenous plants investigated in the 

 Cape Government . Laboratories. These two lists 

 clearly support Dr. Juritz's plea, and leave no room 

 for doubt that researches made v/ith sufficient mate- 

 rial, possibly following, the method so successfully 

 employed by DrJ Power and his collaborators, would 

 yield scientific results of the greatest value. 



Some experiments on the physiology of indigo- 

 yielding glucosides are described by Mr. F. R. Parnell 

 I in the Memoirs of the Department for Agriculture in 

 i India (Botanical Series, vol. vii.. No. 5). An indigo- 

 ' forming glucoside is present in the root and seed of 

 j both irr//;'^i<?a tiuctoria. Br., and W. tomeutosa, R. 



