362 EDWARD S. MORSE ON 



rim and foliated within. It is held firmly to the body wall by the ilio-parietal band 

 (47: l) . This band is divided into several strands, one of which, rather wide, passes 

 directly behind the nephrostome and is attached to the body wall; another, very 

 narrow, passes obliquely backward to the body wall, and still another, a very narrow one, 

 passes obliquely backward toward the median line. The appearance of the inner portion 

 of the nephrostome is shown in 54: 10. The blood in active circulation is seen rushing 

 through the various lacunae which cover the surface of the nephrostome. The whole 

 organ is highly vascular throughout and it would seem that the endothelial lining of the 

 coelomic cavity ensheathed every organ within. The body of the nephridium is a rich 

 orange color, and in L. lepidula the color is so persistent that after a lapse of twenty 

 years, in alcohol, the color through the shell appears just as bright. The body of the 

 nephridium in G-lottidia has an oblong, slightly ovate form, narrowing quite rapidly to its 

 outer termination; it has a few wide longitudinal markings which probably indicate folds 

 within. In L. lepidula (54: 11, 12, 13), the nephridia occupy precisely the same position 

 as in Glottidia. The nephrostome is somewhat different ; in shape it is like a cup with 

 the rim sharply reflected, and just below the rim a deep constriction, and then the wall 

 rounds out again to taper rapidly to the body of the nephridium which it joins at nearly 

 right angles to its axis (48 : 4, 8) . The side of the nephrostome next to the coelomic wall 

 is so closely adherent to it that the wall itself forms part of the border of the nephrostome 

 (see particularly, 54 : 12, 13) . In Glottidia and L. anatina, the rim of the nephrostome is 

 entire, while in L. lepidula the rim merges with the body wall. The folds within the 

 nephrostome (54: 14, 14a) are in the form of loops giving the appearance of a deep 

 fluting. The folds are strongly ciliated and the ciliary action is vigorous. No current 

 was seen to pass through the nephridium ; corpuscles were drawn into the nephrostome 

 only to be whirled out again. Here is an evidence that in some way the animal controls 

 the discharge of matter through it. In Terebratulina, I have followed an egg from its 

 release from the pallial sinus to its entrance into the nephrostome and final discharge at 

 the exterior opening (58 : 4) . There are a few branching lacunae on the walls of the 

 nephridium which is a rich, dark orange, and the color is so pronounced as to show through 

 the shells. The tube follows along the side of the coelomic wall and passing through it 

 obUquely, opens on the anterior wall. The external openings appear as simple slits 

 (48: 4, 8) . The nephridia of L. anatina are not unlike those of Glottidia. The body is 

 thick, wide, flattened, and glandular ; the nephrostomes seem a little more closely appressed 

 to the coelomic wall and the folds converge slightly to the anterior end, as such lines 

 would on an oblong and tapering body. The folds are finer and run parallel to the inner 

 incurving outline of the nephridium. These folds are a rich maroon color. A reference 

 to 55 : 1 will better explain these features. The nephrostome is not so deep as in Glottidia 



