Mr. Osborn gave a note on the habitat of a Chironomus; he said his 

 attention had been called by Dr. B, D. Halstead to certain larva' living 

 in the water contained in the cups surrounding the stem of Silphium 

 perfoliatum. 



The principal form thus found is a species of Chironomidae, nearly 

 transparent and colorless and closely resembling the figures of Chirono- 

 mus oceanicus Packard. The larvae were quite abundant in a large share 

 of the cups examined, as many as forty and fifty occuring in a single cup 

 A number were placed in a glass of water and their transformations 

 watched. Before pupating the larva.' usually came to rest at the surface 

 of the water against the glass, enclosing themselves in a gelatinous mass. 

 Length of pupation appeared to be about two days though not constant 

 in different individuals. 



Before emergence of the imago the pupa assumes a bright silvery ap- 

 pearance from the separation of the outer membrane. The final process 

 of emergence is passed through very rapidly, the imago resting for an in- 

 stant on the surface of the water, and assuming very rapidly the full 

 si/e. The cups must become dry occasionally and it would be interest- 

 ing to know the time required for the entire development of the species. 



Prof. Riley says that most of Prof. Osborn's notes would apply to 

 most of the species: but the developing in the cups Silphium perfoliatum 

 is very curious, and interesting. 



Prof. Cook then gave some notes on the functions of the secretion 

 of Bark lice, Leucanium tilice, Fitch. 



These lice attack many species of our forest and fruit trees. Though 

 the scales on different trees vary considerably in si/e and form, and were 

 similarly peculiar on each species of tree, yet they were doubtless of the 

 same species of insect. Larvae lice from the Linden where they were 



st, transferred to butternut where they were smallest and very con- 

 vex, developed into the peculiar type of the latter tree. These lice se- 

 creted much bitter unwholesome nectar, which attracted the bees. Earh 

 in the spring, it was observed that the Baltimore Oriole ami our two 

 most common Sparrows were feeding extensively on the lice. The birds 

 would take a limb and almost strip it of the lice. When the bees ami 

 wasps commenced to swarm in the trees in quest of the nectar, the birds 

 all left this feeding ground. Soon the flowers lured the bees to more 

 inviting fields, when the birds again commenced to feed on the rapidl) 

 growing scales. The nectar secretion seems surely to serve the insects 

 that secrete it as it attracts the bees, which frighten away the birds. 



» Prof. Riley says this feeding of birds upon the Bark Lice is interest- 

 ing and novel, and has never been observed before, 



Prof. Lintner says this theory of the secretion attracting bees, to 

 keep off the birds was new to him. 



