212 TIJE MONTHLY BULLETIN. 



GENERAL NOTES. 



THE IMPORTATION OF BLACK SCALE PARASITES FROM 



SOUTH AFRICA. 



Through the kindness of Prof. C. P. Lounsbury, Entomologist for the 

 Department of Agriculture of the Union of South Africa, the Insectary 

 has received a number of shipments of twigs of Sparmannia africana, 

 infested with the black scale {iSaisseiia olc(e). To date eleven species of 

 parasites have been reared from this material, two of them in consider- 

 able {{uantities, the others not so abundantly. The parasites are entirely 

 undetermined, and have been submitted to Doctor Howard for names. 

 The two more common species are primary. The status of the remain- 

 ing species has not yet been determined in every case. One we have 

 ascertained to be secondary {i.e., they are parasites of the parasites, 

 therefore injurious), and some of the others undoubtedly will fall in 

 this category. Both primary species emerge from the young scale be- 

 fore the eggs are laid, and hence they should fill a long existing gap in 

 the sequence of the parasites of the black scale and become valuable 

 supplements to the work of Scutellista and Tomocera, which attack the 

 scale after the eggs are laid. 



So far as clinuitic influences are concerned, it would seem as though 

 these parasites should become established in California, as the climate 

 of the Cape is certainly not less severe than that of California, but of 

 course climate is only one of the many factors w^hich make their in- 

 fluence felt in this kind of work. The interrelations between parasite 

 and host are much more intricate in the case of internal parasites 

 such as the two species above than in '"predaceous" parasites like 

 Scutellista. However, from our present knowledge of the situation 

 there would seem to be no valid reason why they should not become 

 established and do good service in the work against the black scale. 



It is of interest in this connection to note that while the Cape is the 

 locality from whence Scutellista was originally obtained for introduc- 

 tion into California, this species in the shipments received is very much 

 less common than the two mentioned above. This is partly accounted 

 for by the fact that when the material left South Africa much of it w^as 

 not in the proper stage for oviposition by Scutellista. However, it is 

 quite evident that these new parasites play an important role in the 

 control of the black scale in South Africa and every effort will be 

 made to get them established in California. 



Professor Lounsbury has for several years maintained that California 

 has not exhausted the possibilities in the way of parasite control of the 

 black scale with the acclimatization of Scutellista, and the interest he 

 has shown in our problems is more than casual. His associate, Mr. C. W. 

 Mally, of Cape Town, was directly concerned in the collection and ship- 

 ping of the recently received material, and the thanks of all Calif ornians 

 is due to Messrs. Lounsbury and Mally for the effort they have made 

 in our behalf. — Harry S. Smith. 



