EUCALYPTUS VIMINALIS. 



Cicadse, according to Mr. Simson, are unknown, bat where species of mnch smaller size are to be 

 met with. Mr. E. P. Eamsay, the zealous Curator of the Sydney-Museum, is of opinion, that also 

 boring coleopterous insects may be active in causing the extrusion of Mellitose. He saw it occa- 

 sionally in large stained lumps, which would remind of the saccharine secretions on the stem of 

 Myoporum platycarpum. Mr. H. Marshall, writing from Angaston to Mr. Otto Tepper, mentions 

 also large flows of " Manna " occurring, when a black Cercopis with white transparent spots on the 

 wings much covered Eucalyptus-stems or branches about BaldhiU, the saccharine mass partially 

 encrusting the bark to a thickness of half an inch like white sugar, and it fell occasionally in such 

 quantity, as to knock down in places the surrounding wheat. Furthermore the Eev. Dr. WooUs 

 noticed, that occasionally also some Mellitose dropped from E. punctata ; while Mr. Duboulay 

 saw it occur on E. loxophleba. Mr. Tepper himself, whose attention I had especially invited to 

 this subject, writes in the journal of the Linnean Society of London, xvii. 109-111 (1883), that 

 Mellitose occurs also on Eucalyptus oleosa and E. odorata. But the small scale-like masses of 

 definite organic form, under which in these instances a psyUaceous larva is lodged, careftilly 

 watched in its development by this enthusiastic naturalist, are different from the amorphous 

 crumblike Mellitose-droppings yielded by E. viminahs, and represents the " Lerp," to which Dr. 

 G. Bennett refers in his valuable volume " Gatherings of a Naturalist in Australia," p. 272 

 (1860) ; and of a similar nature is the saccharine mass in minute shell-like particles, of which 

 Mr. Thos. Dobson, B.A., gave an account in the Proceedings of the Eoyal Society of Van 

 Diemen's Land, i. p. 235-241 (1851), he tracing then already this substance to a Psylla. 



The circumspect Mr. Tepper alludes moreover to a larger kind of " Lerp," to be found on 

 Eucalyptus gracilis, E. uncinata and E. Leucoxylon ; and in a letter, dated Jan. 1882, he speaks 

 also of a coccoid insect, a species of Lecanium, which is concomitant to the viscid sweet sap under 

 the bark of branchlets of E. viminalis and E. rostrata, ants in quest of this sweetness following 

 the mellaginous track. This Lecanium abounds also in many parts of the colony of Victoria. 

 Mr. W. H. Wooster, of Bolwarrah, gave microscopic details concerning Lerp in the journal of the 

 Microscopic Society of Victoria, i. 91, pi. vii. (1882). In bringing together such information, as we 

 possess, on the saccharine secretions of Eucalypts, I should not pass the experiences of the very 

 observant Mr. T. Stephens, M.A., Inspector of Schools of Tasmania, who wrote from Hobart in Feb. 

 1881, that the " Manna " is to be regarded as a simple exudation from the bark of Euc. viminalis ; 

 for although it is there brought out sometimes by the puncturing of the Eurymela Spectrum^i* 

 comes often spontaneously from the twigs, where the bark is fissured and weak. A worthy old 

 colonist, Mr. James Dawson, of Camperdown, found a considerable quantity of Manna adhering to 

 leaves and twigs, which he had experimentally enclosed in a muslin-bag, though the exudation 

 seemed to emanate from insect-punctures previously formed ; thus it was proved, that the Mellitose 

 could not be secreted by the Cicades themselves, as erroneously stiU supposed by many colonists. 

 He moreover found leaves with accidental holes, around which " Manna" was exuded on both sides. 

 This saccharine substance is called by the Aborigines of Western Victoria "Buumbuul"; but they 

 give the same name to the honeylike liquid, on which the smaller insects, already referred to, are 

 located ; this fluid, as the blacks assert, occurring sometimes on the Eucalyptus-stems at river- 

 banks in such quantity, that a bucketfnl could be scraped off" from one tree. That the sap even of 

 the leaves of E. viminahs is rich in saccharine matter was proved by an analysis, under my 

 direction made by Mr. L. Eummel. The percentage, as computed for dried leaves (rather more 

 than half of the weight of fresh leaves being moisture), turned out as follows : — -43 Eucalypto- 



