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VI. On the (Economy of a new Species of Saw-fly. By John Curtis, Esq., F.L.S. fyc. 



Read January 15, 1850. 



XHE general attention which is now paid to Natural History almost daily brings to light 

 some hidden treasure to interest the public and satisfy the inquiring mind. The subject 

 of this communication appears to be one of these novelties, for a knowledge of which I am 

 indebted to a friend who has lately been admitted a Fellow of the Linnean Society. 



The insect alluded to belongs to the family Tenthredmidce, a group of Hymenoptera so 

 different in oeconomy from the rest of that Order, that some entomologists have been 

 inclined to separate it from the aculeate families. In general habits the Saw-flies resemble 

 the Lepidoptera in their second or larva-state, usually feeding on the leaves of plants ; but 

 there are many instances of their living on the pith in the stems of shrubs *, in fruit f, 

 and evidence is not wanting to lead to an opinion that some are parasitical J, whilst others 

 form galls §. 



It is not my intention now to enter farther upon these curious anomalies, but to give 

 the ceconomy and descriptions of the species before us, which I propose naming, in honour 

 of its captor, Viscount Goderich, 



Selandria Robinsoni. 



On the 19th of June, 1848, Lord Bipon's gardener at Putney, Mr. Joseph Jerwood, sent 

 me, by the request of Lord Goderich, forty or fifty caterpillars the size of those figured, 

 which for two years had devoured the leaves of the Solomon's Seal ; eating enormous holes 

 in them, and leaving only portions of the fibres, as exhibited in the drawing (fig. 1) . During 

 the present year Lord Goderich forwarded to me the following memoranda : — 



" Three years ago (1846), about the month of July, I observed that the only plant in 

 our garden of Solomon's Seal (Convallaria multiflora, L.) was completely covered and 

 almost entirely devoured by larvae, which I easily perceived must belong to the family of 

 Tenthredinidce. They had at that time almost consumed the entire membrane of the 

 leaves, and many bf them were even feeding on the stalks. In a short time after, they 

 had eaten the plant nearly to the ground, leaving only the stronger branches. They did 

 not appear to touch any of the surrounding flowers or foliage, but upon the Solomon's 

 Seal they were extremely numerous, amounting I should think on one small plant to full 

 one hundred. 



" The next year they re-appeared in the same numbers, and then, being much struck by 



* Dr. Maclean has discovered a larva in the succulent shoots of rose-trees, which may possibly be the offspring of 

 Emphytus varipes, a species I have reared from the stems of dog-roses. 



t I have found the larvae of Selandria testudinea 1 feeding in apples, and of S. Morio in plums. 



X Bielocerus Ellisii, Linn. Trans, vol. xix. p. 249. § Nematus internes causes the rosy galls on willows. 



