ii8 The American Geologist. February, 1903. 
external covering belong literally to one and the "same struc- 
ture." 
"In life, the pallium in the Lingulidae exhibits on its inner 
surface and around its borders a rich brown pigmentation. 
In the anterior portion of the pallium, this pigmentation as- 
sumes a definite color pattern. It is ])ossible that these mark- 
ings may ofifer characters for s]>ecific determination, though 
they would have to be made out from living specimens, as in 
alcohol these colors entirely disappear. The perfect symmetry 
of this pattern on each side of a median line, the rich brown 
color of the design in contrast to the pure white or greenish 
tinge of the remaining surface, with the rosy tints of the red 
circulating- fluid in the lacunae, render the pallium a most 
beautiful object in life. * '•' '•' * The most conspicuous 
feature of the borders of the pallium are the crowded setae 
which spring from setigerous follicles somewhat deeply buried 
in the pallium." 
"Viewing Glottidia from the dorsal surface, a treble, gourd- 
like outline is distinguished, which represents the boundaries 
of the coelomic wall. All markings within this outline are 
caused by the muscles, stomachal glands, genitalia, digestive 
tract, etc. All markings outside this outline are made by the 
brachia and the sinuses and lacunae of the pallium. 
"The region enclosed by the dorsal and ventral pallium, 
fore and aft and laterally, communicates freely with the sea 
water. The treble, gourd-shaped figure may be defined as 
follows : the anterior portion embraces the region of the dorsal 
attachment of the lateralis muscles and the pharynx and 
oesophagus, and might be called the peri-oesophageal cavity ; 
the second gourd embraces the stomach, a portion of the stom- 
achal glands, and the first and second anterior occlusors, and 
may properly be designated as the perigastric cavity ; the third 
and largest gourd, forming the main coelomic cavity, is nearly 
circular in shape and includes the intestine, a portion of the 
stomachal glands, the nephridia and genitalia, and the oblique 
and posterior occlusor muscles ; this region may be called the 
perivisceral cavity" (pp. 349-351). 
PaUial sinuses and blood eirculation. — Because these sin- 
uses are so often impressed both upon articulate and inarticu- 
late brachiopods, it is deemed appropriate to quote Morse's 
description of them at length. 
