235 



eacli type ; if an animal approach nearer perfection because, 

 for instance, it be part fish and part reptile, or if a structure 

 part animal and part vegetjible be more perfect than the plant, 

 then is the cell the ty{)e of perfection, combining as it does prop- 

 erties belonging to both kingdoms ; he considered perfection, not 

 the union of different types, but specialization in each particular 

 type. 



Prof. Agassiz considered perfection to mean an embodiment of 

 the highest combinations, the most complex representation of life. 

 The embryo fish presents features of its type superior to those of 

 the adult fish ; the tendency to specialization increases Avith its 

 growth, and the animal at last becomes only a fish, losing its em- 

 bryonic type of the higher vertebrates. As a generalization or 

 philosophic conception, the vertebrate egg is superior to man him- 

 self, inasmuch as it embodies all that may be produced from it. 



Mr. Scudder presented by title a description of Hoplo- 

 campa nibi by the late Dr. T. W. Harris, with remarks 

 on its history by Noyes Darling, Esq., in letters to the 

 same, as follows : — 



Family Tenthredinid^. 



Genus Selandria, (Leach.) 

 Sub-genus Hoplocampa, (Hartig.) 



Selandria (H.) ruhi (Harris).* Black; a spot on each side 

 of the collar, middle of the dorsum, and legs, dirty yellow ; hind- 

 most tarsi dusky ; wings smoky. Length of the body nearly one 

 fifth, expansion of wings one half of an inch. 



Larva, green : 6 dorsal rows of tubercles bearing 2 black bris- 

 tles, and 4 lateral rows on each side bearing white bristles ; most 

 of these tubercles have 2 bristles, some have 3, and the anterior 

 ones of the first segment have 4. or 5 each, — the tubercles alter- 

 nate in the rows. Each segment, therefore, has 14 setigerous 

 tubercles ; along the lower margin of the body are a few more 

 single bristles, or short tubercles, irregularly placed. Bristles 

 not barbed, /^th of an inch in length. 



* See Address upon Injurious Insects, by Noyes Darlinjr, p- 13. New Haven, 

 1845. New England Farmer, i., p. 164, 1849; ii., p. 33, 1850. 



