102 THE NAUTILUS. 



Barnes, and the umbonal ridge is not as well defined ; the laterals 

 are shorter and the shell is more transverse; the undulations cross 

 the umbonal elevation instead of running parallel with it and the 

 beaks are less prominent. Compared with U. multiplicatus Lea our 

 shell is subtriangular in outline instead of trapezoidal, always more 

 winged and shorter, and the laterals are also shorter ; the pos- 

 terior slope is more gradual and the umboues are not flattened, and 

 are more depressed than in that species, the highest point being 

 nearly in the centre of the disk where there is quite a prominence; 

 the cardinals are more depressed and the pustulations extend more 

 generally over the anterior portion. 



In old specimens the sculpture diminishes almost to smoothness 

 except in the superior parts, the umbonal elevation becomes obsolete 

 and the shell is more elongated. Twenty specimens of all ages 

 have been compared with specimens of corresponding ages of all the 

 allied species, and comparisons with the type forms in the National 

 Museum have been made through the kindness of Mr. Charles T. 

 Simpson. 



MODIOLA PLICATULA LAMARCK AN EXTINCT LOCALITY. 



BY R. E. C. S. 



Fifty years ago, more or less, that part of the city of Boston 

 which includes the Public Garden aud the grand array of fine 

 avenues and streets that reach out east and west, north and south, 

 and form what is locally known as the Back-Bay Section, was a 

 portion of a larger territory, some six hundred acres, of wet and dry 

 marsh and mud flats, that extended from Charles Street at the foot 

 of " Boston Common," to Roxbury. A considerable portion of 

 this region was inhabited by a peacefully disposed and quiet com- 

 munity. In numbers this community, certainly if counted, would 

 have made a bigger showing than the census of human bipeds that 

 constituted the population of Boston at that time. Though numer- 

 ous, they were not influential and had no social status among the 

 best people of " Modern Athens." 



This may have been owing to the fact that their ancestors did not 

 come over in the Mayflower, or later with Winthrop and Salton- 

 stall. No, they were here, or their forefathers were, long before the 

 advent of the " Pilgrim Fathers ; " they had an older claim, prior- 



