TKANSACTIONS OF SECTION fi. 933 



three species: one of these, T. rubra, Pat. and Lagerh,,' is described as growing 

 on a coccus. The Ceylon forms, two iu numher, agree fairly closely with the 

 description of T. rubra. One, with deep pink perithecia, was found on a species of 

 Aleurodes, the other, with pale brown perithecia, on a species of Aspidiotus. 



Aschersonia, — This genus, chiefly tropical, and consisting now of about nineteen 

 species, has usually been taken to be a leaf-infesting one. Webber - has shown 

 that it may also be entomogenous. It is quite possible that species hitherto 

 regarded as growing on leaves and stems are in reality parasitic on scale-insects 

 occurring on these parts of plants. The Ceylon forms have been formed on species 

 of Aleurode-i and Lecanium. 



Along with one of these Aschersonias on the same kind of scale are flattened 

 circular brown fungous pustules, which are similar in structure to what Webber 

 names as the * brown mealy-wing fungus.' ^ In neither case has any trace of 

 spore-formation been found. 



Cephalosporium. — The fungus referred to previously as found by Zimmermann 

 on the green bug has been named by him provisionally as Cephalosporium Lecanii, 

 Specimens practically identical with this have been obtained in Ceylon on the 

 same scale on the cotfee and other plants, also on two other species of Lecanium. 



Vertidllium. — The species V. heterocladium* described by Penzig as occurring 

 on the dead bodies of Lecanium hesperidum on leaves of the lemon, is the single 

 instance found of such a habitat for this genus. The Ceylon member was dis- 

 covered on the same scale and on the same bamboo as possessed the Nectria, 

 mentioned above. As a rule the Nectria was confined to the upper and the 

 Vertidllium to the lower surface of the leaves. Possibly the two may be 

 connected. 



Microcera. — This genus, closely related to Fusarium, was established by 

 Desmazieres ^ in 1848 for a fungus {M. coccophila) discovered on a scale-insect. 

 Later it was shown to be the conidial stage of SphcBrostilbe coccophila.'' Another 

 species, M. rectispora, Cooke and Mass.,^ has been found associated with a coccus 

 on the orange in Australia. The Ceylon types occur on three genera of the 

 Diaspidinse. One of them is probably the conidial stage of a Calonectria. 



Campsotrichum. — The fungus referred to this genus was discovered growing 

 on a scale {Chionasjns Aspidistra) on a palm. It has not yet received a very close 

 examination, but seems to agree best with this genus of the group Dematiacese 

 of the Fungi imperfecti. 



Mr. Green has also passed on to the author specimens of this class of fungi 

 received from other countvies,y\z., Aschersonia from India, Sumatra, and Java, and 

 Microcera from West Africa and Mauritius. 



Thus it seems that fungi infesting scale-insects have an extensive distribution, 

 especially in and near the tropics. That they are the true cause of the death of 

 the insects there seems little doubt. 



I 



FRIDAY, SEPTEMBER 7, 



The following Papers were read : — 



1. On the so-called Optimum Strength ofCO^ for Assimilation. 

 By Dr. F. F. Blackman. 



' Patouillard et Lagerheim, ' Sur Champignons de I'Equateur,' Bull, de la Soc, 

 Mycol. de France, vol. ix. 1893, p. 154. 



- Webber, lac. cit. 



^ Webber, loe. cit., p. 27. * 



* Saccardo, S.F., vol. iv. 188G, p. 1.51. 



° Desmaziferes, 'Plantes Cryptogames Nouvelles,' Ann. dcs Sc. Kat., 3rd ser., 1848, 

 p. 359. 



' Tulasne, Carpologia, vol. iii. 1865, p. 105. 



' Saccardo, S.F., vol. x. p. 731. 



