108 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



lines on either side of the dark dorsal area. At this age they look 

 somewhat as though they had been covered with a fine white powder. 



May 9. Fourth moult Length of larva 11 to 14 mm.; head 1.40 to 

 1.50 mm. in diameter. Dark dorsal area gradually disappearing. 



May 12. Fifth moult. Length of larva 14 to 16 mm. ; head 1.50 to 

 1.60 mm. in diameter. By this time the larvae have assumed a bluish 

 smoky color, darkest along the dorsal aspect, ventral lines and prolegs 

 yellow, body distinctly transversely wrinkled, tips of thoracic legs 

 brown, eyes black, head smoky white. After the fifth monlt the 

 larva apparently does not feed again, but leaves the tree and enters the 

 soil, where it constructs an earthen cocoon about one-half inch long, 

 in which it remains unchanged until the spring of the following year. 



Observations for four successive years prove this sawfly to be 

 single brooded. 



The species in question was first observed attacking ash at 

 Manhattan, Kansas, in 1888, by Mr. C. L. Marlatt, while 

 studying the life history of the ash sawfly Tomostethus bardns 

 (Say). Mr. Marlatt recognized it to be an undescribed 

 species and on page 195 of the First Annual Report of the Kansas 

 Experimental Station, Division of Entomolog-y, gives a good 

 drawing illustrating two views of the head of the larva. Adults 

 of this species, as well as those reared by the writer, have been 

 examined by Mr. S. A. Rohwer, who identifies them as 70- 

 mostethus multicinctus (Roh.). In the original description 1 

 this species was described from material collected May 6 at 

 Washington, D. C., and April 27, Falls Church, Virginia, by 

 Mr. Nathan Banks. 



In studying the various stages of the sawfly it was soon ob- 

 served that a great many of the larvae were apparently sick 

 and dropping from the trees. The trunks of the ash and 

 sycamore, and in fact even stakes in close proximity to the 

 trees from which they had fallen, were more or less whitened 

 by the presence of sick larvae which were attempting to get 

 back on the foliage. So conspicuous were these larvae that it 

 was not uncommon to see groups of pedestrians gazing Curi- 

 ously at the infested trees. In order to ascertain if possible 

 the cause of this apparent sickness, sawflies were submitted for 

 examination to Mrs. Flora W. Patterson, who reported that 

 the death of the larvae had been brought about by one of the En - 

 tomophythora^, but as the fungus was only present in the my- 

 celial stage it was impossible to give a specific identification. 



EXPLANATION OF PLATE VII. 

 Tomostethus multicinctus. 



FIG. 1. Female. FIG. 3. Larva- feeding on leaves. 



2. Male. 



'Can. Ent., XLI, p. 90 (1909). 



