204 



I'ROCEEDINOS OF THE NATIONAL MVHEUM. 



VOL. 40. 



Webb collection; altitude, 25.5 mm.; diameter, 12.5 mm. Busuanga Id. 



Webb collection; altitude, 25.0 mm.; diameter, 12.5 mm. Busuanga Id. 



Webb collection; altitude, 26.2 mm.; diameter, 12.5 mm. Busuanga Id. 



Webb collection; altitude, 27.0 mm.; diameter, 13.0 mm. Busuanga Id. 



Webb collection; altitude, 24.7 mm.; diameter, 12.7 mm. Busuanga Id. 



Webb collection; altitude, 25.0 mm.; diameter, 13.0 mm. Busuanga Id. 



Webb collection; altitude, 26.0 mm.; diameter, 13.1 mm. Busuanga Id. 



Webb collection; altitude, 25.7 mm.; diameter, 12.6 mm. Busuanga Id. 



Webb collection; altitude, 25.3 mm.; diameter, 13.0 mm. Busuanga Id. 



Webb collection; altitude, 25.3 mm.; diameter, 12.6 mm. Busuanga Id. 



Webb collection; altitude, 25.3 mm.; diameter, 12.4 mm. Busuanga Id. 



Webb collection; altitude, 26.0 mm.; diameter, 13.0 mm. Busuanga Id. 



Webb collection; altitude, 24.5 mm.; diameter, 12.1 mm. Busuanga Id. 

 Average, altitude, 25.71 mm.; diameter, 13.04 mm. 

 Greatest, altitude, 27.4 mm.; diameter, 13.4 mm. 

 Least, altitude, 24.5 mm.; diameter, 11.3 mm. 



SCHISTOLOMA (HOLOLOMA) QUADRASI CORONENSIS, new subspecies. 



This subspecies is uniformly larger than quadrasi. We have seen 

 thirteen specimens from the Island of Coron, which give the follow- 

 ing measurements. This is probably what was listed as Coptochilus 

 quadrasi rhodocliilus by von Mollendorff, which is a nomen nudum. ^ 



Cat. No. 296611, U.S.N. M.; altitude, 28.4 mm.; diameter, 14.0mm. Coron Id. (type). 



Webb collection; altitude, 28.3 mm.; diameter, 13.4 mm. Coron Id. 



Webb collection; altitude, 28.1 mm.; diameter, 13.3 mm. Coron Id. 



■Webb collection; altitude, 27.5 mm.; diameter, 13.0 mm. Coron Id. 



"Webb collection; altitude, 28.5 mm.; diameter, 13.8 mm. Coron Id. 



Webb collection; altitude, 29.0 mm.; diameter, 14.0 mm. Coron Id. 



Webb collection; altitude, 30.0 mm.; diameter, 13.2 mm. Coron Id. 



Webb collection; altitude, 28.0 mm.; diameter, 14.3 mm. Coron Id. 



Webb collection; altitude, 27.9 mm.; diameter, 14.5 mm. Coron Id. 



Webb collection; altitude, 27.0 mm.; diameter, 13.3 mm. Coron Id. 



Webb collection; altitude, 27.1 mm.; diameter, 13.0 mm. Coron Id. 



Webb collection; altitude, 27.0 mm.; diameter, 13.2 mm. Coron Id. 



Webb collection; altitude, 26.4 mm.; diameter, 13.3 mm. Coron Id. 



Average, altitude, 28.4 mm.; diameter, 13.56 mm. 



Greatest, altitude, 30.0 mm.; diameter, 14.5 mm. 



Least, altitude, 26.4 mm.; diameter, 13.0 mm. 



EXPLANATION OF PLATE 51. 



Fig. 1. Schistoloma (Schistoloma) alia rnmdoroensis Bartsch, profile (type). 



2. Schistoloma {Schisloloma) mcgrer/ori mcgrcgori Bartsch, basal view (type). 



3. Sddstoloma {Schistolonia) alia vnndoroeusis Bartsch, basal view (type). 



4. Schistoloma (Schistolovia) mccjregori vtcgrcgori Bartsch, profile (tyjje). 



5. Operculum of Schistoloma, inner ^•iew. The light area represents the muscu- 



lar attachment; the central ring, the fusing of the various laminae. 



6. Same as above, lateral view, to show the arrangement of the laminae. 



7. Same as above, exterior view, showing the edge of the last lamina, the inner 



circle indicating the fusing points of all the laminae. 



8. Schistoloma {Ilololoma) ciuadrasi quadrasi Hidalgo, profile. 



9. Schistoloma {Schistoloma) alta alia Sowerby, basal view. 



10. Schistoloma {Ilololoma) quadrasi quadrasi Hidalgo, basal view. 



11. Schistoloma {Schistoloma) alta alta Sowerby, profile. 



1 Abh. Ges. Gorlitz, vol. 22, p. 186, 1898. 



