414 
The Ohio Naturalist. 
[Vol. Ill, No. 6, 
serrate, extending posteriorly two-thirds of length of median lobe, 
and separated from it by almost its own width. Outer lobule 
rudimentary, rounded. Third lobe rudimentary ; lobules faintly 
serrate. The gland-spines are arranged as follows: i, i, i, i, 
3-4 ; large and conspicuous, decreasing in size toward the median 
lobes. Spines on dorsal surface are arranged as follows : 1st on 
base of median lobe, laterad of center ; 2nd at base of second lobe, 
between the lobules ; 3rd at base of third lobe ; 4th about two- 
thirds of distance to penultimate segment, posterior from the 
fourth gland-spine. On the ventral surface the spines are shorter 
and located just laterad of the corresponding dorsal spine. First 
and second rows of dorsal gland-orifices are absent ; third row rep- 
resented by 3-5 in the anterior and 3-6 in the posterior group ; 
fourth row with 2-4 in anterior and 5-7 in posterior group. 
Median group of circumgenital gland-orifices , 4-10 ; anterior later- 
als, 15-21 ; posterior laterals, 8-14. 
Habitat: Abundant on Gleditsia triacan/hos (Honey Locust), 
at Columbus, Ohio. 
[ The author wishes to thank Prof. Cooley for his expert opinion on this species, and 
also for his many favors.] 
EXPLANATION OF PLATE. 
Fig. i. — Scale of female. Fig. 2.— Scale of male. 
Fig. 3. — Pygidium of female. Fig. 4. — Part of Fig. 3, enlarged. 
