66 lAnnean Society. [Jan. 15, 



Read a Paper " On the Economy of a new species of Saw-fly." By 

 John Curtis, Esq., F.L.S. &c. &c. 



This species, which belongs to the genus Selandria, was taken by 

 Lord Goderich in his father's garden at Putney, where its larvae 

 were first observed in July 1846, on the Solomon's Seal (Convallaria 

 multiflora, L. ?). When first noticed. Lord Goderich states, they had 

 almost consumed the entire membrane of the leaves, and many of 

 them were feeding on the stalks ; and in a short time after they had 

 eaten the plant nearly to the ground, leaving only the stronger 

 branches, but not destroying the plant itself. The number on one 

 small plant was full a hundred ; and the next year, and again in 1848, 

 they reappeared in equal numbers. In 1849 their 'numbers were 

 fewer. Mr. Curtis gives a detailed description of the caterpillar, 

 which on the 28th of June (when many of them had cast their last 

 skins, which remained sticking to the leaves) were nearly f of an 

 inch in length. They disappeared in succession, burying themselves 

 from 2 to 4 inches deep in the earth, where they formed small oval 

 cocoons like a coating of glue, but often perforated in different places. 

 On the 30th of April in the last year, Mr. Curtis succeeded jin 

 breeding a male fly ; another male and two females were hatched on 

 the 3rd of May ; and these were succeeded by several more of the 

 latter sex. They were as black as ink, and appear ^to be allied to 

 Selandria fuligiiiosa, Schrank, but the male antennae approach those 

 of Cladius. A full description of both sexes is given, and the species 

 is named by Mr. Curtis after its discoverer, Selandria Robinsoni. 



The paper was accompanied by drawings, illustrating the struc- 

 ture of the insect ; and was concluded by some remarks on the 

 characters and affinities of the genus Selandria. Although the 

 elongated antennae of the species described resemble those of 

 Nematus, and still more those of Cladius, it is not only distinguished 

 from those genera by its divided marginal cell, but the heavy habit 

 of the females especially and the characters of its trophi, which are 

 intermediate between Athelia and Tenthredo, indicate the groups to 

 which it is naturally allied. The author regards the number of 

 discoidal cells in the inferior wings as furnishing good characters for 

 the distinction of the genus Selandria into sections as follows : — 



1 . With two discoidal cells, the marginal cell receiving one trans- 

 verse nervure. — Example S. serva, Fabr. 



2. With both transverse nervures united with the marginal one. — 

 Example S. stramineipes, Klug. 



3. With one discoidal cell. — Example S. Robinsoni. 



4. With no discoidal cell. — Example S.fuliginosa, Schrank. 



