PLATE 10. 
From photographs made by C. E. Beecher. 
Fig. I. — Isotelus latus Raymond. Ventral surface of the specimen in the Victoria 
Memorial Museum at Ottawa, Canada. Note the large, club-shaped coxopodites and the 
more slender endopodites. The first large coxopodite back of the hypostoma belongs to 
the last pair of cephalic appendages. The coxopodite of the appendage in front of it is seen 
turning in beneath the tip of the hypostoma. x 2. 
Fig. 2. — Isotelus maximus Locke. The ventral side of the specimen described by Mickle- 
borough and now in the U. S. National Museum. The tips of the hypostoma may be seen 
at the front, and the first two pairs of coxopodites behind them belong to the last two pairs 
of appendages of the cephalon. Note how much stronger the coxopodites are than the en- 
dopodites. The appendages of the pygidium show but poorly, x 1.45. 
