1893.] 



NAIM'RAL SCIENCES ()!•' I'l I I I. A I >KI.I'I I I A . 



40:'» 



REPORT OK THE COMMITTEE ON THE HAYDEN MEMORIAL 

 GEOLOGICAL AWARD. 



The Committee on the Harden Geological Memorial Award in 

 fulfilling the trust confided to it by the Academy recommends that 

 the Hayden Memorial Medal and the balance of the interest arising 

 from the fund he awarded tliis year to Thomas Henry Huxley, 

 Ph. I)., LL. U., D. C, L., F. R. S., F. L, S., F. G. S., Professor 

 of Biology in the Royal College of Science of London, in recognition 

 of the great services which he has rendered to science and especially 

 to geology, during the long period of his valuable original researches. 



In doing this the Committee is but acting as the agent of the 



Academy, but it desires in addition and on behalf of its members 



whom his labors have assisted and enlightened, to add a tribute of 



its own to the high scientific value of Dr. Huxley's achievements. 



Persifor Frazer, 

 Angelo Heilprin, 

 J. Peter Lesley, 

 Ben.l Smith. Lyman, 



Committee. 



Thysanophora coloba u. sp. — Mr. H. A. Pilskry exhibited 

 specimens of a minute land snail from Polvon, Nicaragua, which hail 

 been for many years in the collection of the Academy under the name 

 Helix wilhelmi Pfr. He stated that it was not that species, but a 

 new form of the genus Thysanophora, for which the name coloba was 

 proposed. He defined the species as follows: 



Sp.char.: — Shell minute, depressed, with slightly con- 

 oidal spire ; thin and fragile, light reddish horn colored. 

 Umbilicus open but narrow, one-sixth the diameter of 

 the base ; whorls o], convex, the first one smooth, the 

 others very finely and closely striated, the stria- 

 oblique, arcuate, on the last whorl becoming small, 

 wrinkle-like riblets; Under a high magnification (50 

 diameters) an excessively close, fine sculpture of revolv- 

 ing lines becomes visible. Aperture rounded-lunate, 

 oblique; lip thin, sharp, the columellar margin dilated. 

 Alt. 1-16 mm., diam. 1 -84 mm. The specimens are 

 from Polvon, Nicaragua, collected by the McNeil ex- 

 pedition. This species seems nearly allied to T. guate- 

 malensis C. and F. , but it is much more depressed, 

 more widely umbilicated and smaller. 



Henry C. Mercer and Susanna M. Gaskell were elected members. 

 The following were ordered to be printed: — 



(3 



