Report of thp] Dkpartment of Agriculture. 547 



])uriii<^' the jx'iiod under l•e^'ie\v no suitable myc dog'ist was obtain- 

 able to take charo'e at the Natal Herbarium, Durban, and in 

 consequence all investii^'ation work at this station was at a standstill. 



The Government Mycoloo-ist at Capetown continued liis work on 

 the causes of wastai>"e in export citrus iruit; the results obtained were 

 embodied in bis report jjublished in liulletin No. 1 of 1922. 



Sprayino- experiments on the control of pear scab, or FusicJaditiin, 

 were carried out at St clb-nbosch and Somerset West. The results 

 show that o-ood control can be ol)lained provided that sufficient appli- 

 cations are made at the ri(/lit time. The winter .stao'6 of the pear 

 organism was observed for the iirst time in South Africa, and a 

 preliminary investi^'at ion made on the periodicity of the winter spores 

 and the correlation between tlieir liberation and the first outbreaks of 

 /''usirladium. 



()ther plant diseases which are being- kept under observation in 

 ihe western Cape districts are the following-: — Silver leaf disease; 

 :ii;i)lc mildew, which is especially tioublesome near Hobertson and 

 Montagu : " vrotpootje " of wheat ; and certain loquat dise.ises. 



2. \nti(jn(il Heilxiiium. — During the year 5599 specimens of 

 tiowering plants were acquired b\ purchase, donation, or exchange, 

 and 973 specimens sent in exchange or donated tj other herl)aria. 

 ( )ver 2o()() determinations of plants were made during the year. In 

 Ihe crv];togamic section, 7i)9 specimens were incorj)orate(l and con- 

 sidcMable })rogri'ss w;is made in the preparation of an exchange 

 colb'ction. An uji-lo-date rei'erence index was coni])iled of the 

 1000 odd geneia of lungi rei)resented in the herbarium, with 

 special reference to their systematic position. The necessity for this 

 arose owing- to the recent revision of many grouns and the lack of any 

 co-ordinated reference v\-ork on the uuitter. In the Botanical Museum 

 118 specimens of economic interest were incorporated. Among the 

 donations received special mention should be made of an exhibit of 

 Para rubber from the Research La])oratory, Petaling, and of tea from 

 the Rjyal Botanic Gardens, Peringuay, Ceylon. 



3. Grasses. — Miss Stent spent two months at theKew Herbarium 

 on a special study of South African grasses, taking- with her for deter- 

 mination some 500 specimens from the National Herbarium and 300 

 to 400 from Rhodesia. It was found that certain genera badly need 

 revision, and copious notes were made for future work along these 

 lines. A large number of collections of indigenous grasses were 

 named (including those made by Dr. Pole Evans on his frequent trips 

 to the bushveld, by officers of the Division of Veterinarv Research, and 

 l)y other collectors, notably Mr. Eyles, of Rhodesia). Certain new- 

 species were found in these collections and are being- described. 



4. Botanical Siirrcij. — A meeting- of the Botanical Survey Com- 

 mittee was held at Grahamstown in November, 1921. Several matters 

 of importance affecting the work of tlie survey were discussed. The 

 Directo]- rei^orted that the Minister had auth.u-ized the jjublication of 

 a Botanical Survey Guide, and also of Dr. Schchiland's paper on the 

 Cyperaceae. Dr. Bews read an interesting paper dealing with the 

 (luestion of slope in regard t(- the vegetation of the Natal coast, and 

 also spoke on the subject of the origin, migration, and evolutionary 

 tendencies of the Natal flora. He also outlined the wjrk he had done 

 in connection with the Pica Survey. Dr. Marloth g-ave an account of 

 his trip with the Veterinary Research Officer from Grahamstown in 



