APPENDAGES 



237 



each consisting of a single flagellum formed of short conical joints. 

 The other cephalic ap- 

 pendages increase in 

 size successively. At 

 present the second and 

 third pairs are not 

 satisfactorily known, 

 Lut appear to have 

 been similar to the 

 fourth and fifth pairs. 

 The second pair is 

 attached at the level 

 of the posterior end 

 of the hypostome. The 

 fourth and fifth pairs 

 have large, triangular 

 coxopodites which 

 served as gnathobases, 

 their inner edges being 

 denticulate ; the endo- 

 podites consist of stout 

 joints ; the exopodites 

 are slender, and bear 

 setae which are often 

 arranged in a fan-like 

 manner. 



The first pair of 

 appendages appear to 

 be antennules, whilst 

 the second pair prob- 

 ably represent the an- 

 tennae, the third pair 

 the mandibles, and the 

 fourth and fifth pairs 



the maxillae of Other FIG. 142. Tnarthms becki, Green, x 2. Utica 



f!rn<d-ar>pn Thp anr>pml slate (Orclovician), near Home, New York. A. 



6a - - Ventral surface with appendages ; Ep, metastome ; 



ages of the thorax and Hy, hypostome. B, second thoracic appendage ; 



I- i j-tf en, endopodite ; .c, exopodite, x 12. (After 



pygidium do not differ Be ' echer / 



essentially from the two 



posterior cephalic appendages. Those on the anterior part of 



en / 



