THE NAUTILUS. 115 



lection. Of these rarest species Marietta sinithii [Martesia car- 

 ibaea] is the only one now in the Am. Mus. (local) collection. 



Davis, W. T., Variations of My a arena-rid on the shores of 

 S. I., Nat. Sci. Ass. of S. I., Proc., vol. 1, p. 20, 1885. 



On rocky ground the valves are of moderate size, the ends 

 often broken and the exterior corrugated; in sandy ground the 

 valves are very thin, of even growth, the markings complete, 

 they are beautiful in form and color and of largest size; in peat 

 the valves are very much deformed and much rounded. 



On the distribution of Litorina littoralis, idem., vol. 1, p. 61, 

 1888 and vol. 3, p. 50, 1893. 



It was first noticed by Mr. Hollick at the Narrows in 1888. 



Smith, S., & Prime, Temple, Pteport on the Mollusca of L. I, 

 and its Dependencies, Ann. Lye. Nat. Hist. N. Y., vol. 9, pp. 

 377-417, 1870. 



Herein Odostoniia trifida, 0. bisutural-is, Polinices triseriahi, 

 Paludestrina mlnuta, Litorina rndi, L. littoralis and Lacuna, 

 vincta are recorded as having their southern limit at S. I. This 

 is certainly not the case with the first four species. 



From these records one is struck by the decrease in the fauna 

 accompanying the expansion of the city. One of the important 

 factors in the extermination of the less hardy species is the 

 crowding of the beaches for miles beyond the city limits with 

 cottages and bungalos and the accompanying gasoline boats. 

 This evil is obviated by the purchase of the land for large 

 private estates and clubs. 



VITREA (PARAVITREA) MULTIDENTATA AND LAMELLIDENS. 



BY GEO. H. CLAPP. 



Having recently received a specimen of V. lamellidens from 

 Norway, Me. , I have gone over my collection with the idea of 

 trying to find if lamellidens as it occurs in the north is really the 

 same as the typical form from the Great Smoky Mountains or, 

 as Dr. Pilsbry suggests in Proc. Acad. Nat. Sci., 1903, p. 209, 

 merely "accelerated individuals (of multidentata), sporadically 



occurring. ' ' 



