272 NEW YORK STATE MUSEUM 



post-palmars — all the plates, superior to the axillary palmars in the arms of 



crinoids 

 prehensile — adapted for seizing 

 preoral — situated in front of the mouth 

 produced — drawn out, elongated 

 proliferous — reproducing buds from the calyx 

 protoconch — embryonic shell of a cephalous molluscan 

 proximal — nearest or basal portion 



pseudocolumella — false columella in corals, formed by a twisting of the septa 

 pseudodeltidium — false deltidium (Spirifer), formed by union of the 



two deltidial plates 

 pseudosepta — septa-like ridges of Chaetetes, etc., the projecting ends of the 



lunaria in the cells of certain bryozoa 

 pseudotheca — false wall or theca in some corals, formed by the expansion of 



the outer margins of the septa 

 punctate — dotted, with scattered dots or pits 

 pustule — small blister-like elevation 

 pustulose — bearing pustules or projections 



pygidium — posterior or tail portion of the carapace of trilobites 

 pyramidal — having the form of a pyramid 

 pyriform — pear-shaped 

 pyriformis — pear-shaped 



quadrangular — four angled 



quadrate — with four equal and parallel sides 



quadrifid — cut into four points 



quadrilobate — bearing four lobes 



quadriplicate — with four folds 



quincunx — five objects arranged in a square with one in the middle 



rachis — central stem of a frond in bryozoa, etc. 



radials — main plates of the calyx of a crinoid, resting on the parabasals, and 



alternating with them 

 radii — ribs or striations diverging from the beak of a shell 

 ramose — branching 

 ramus — branch of a skeletal structure 

 reniform — kidney form 

 resilium — internal cartilage or compressible substance in the hinge of pelecy- 



pods 

 reticulated — like a network 

 retractile — capable of being withdrawn 

 retral — backward 



rhynchonelloid — resembling Rhynchonella 



root — expanded basal portion of a crinoid stem, used for fixation 

 rostrum — a beak or snout 

 rugosa — an old name for the Tetracoralla 



