4 THE NAUTILUS. 



ing four jetties, one below and three above the ledge referred 

 to, but the erosion apparently still continues. The following 

 notes are based chiefly on those species that were very limited 

 in their distribution and which therefore may have become 

 locally extirpated by the many changes affecting their environ- 

 ments. A list of about 200 species published by the writer in 

 1890 l forms the basis of some of the following remarks. 



Macrocallista nimbosa Sol. (1) This is the Callista gigantea 

 Gmel. of my list. It was found only in the shoal water at the 

 head of the " Lagoon," seeming to prefer the quiet water, as I 

 never found a trace of it on the ocean beach. At most only six 

 or eight specimens were found, and many of these were broken, 

 probably by the large ray or "clam cracker" as the butterfly 

 ray (Pteroplatea madura} is called by the fishermen. 



Donax obesa d'Orb. (2) This little chunky species was 

 formerly common on the sand bars at the mouth of the 

 "Lagoon," where there was a slight shifting of the sand at 

 every tide. The larger species, Donax variabilis Say, was (and 

 probably is) exceedingly abundant on the ocean beaches, 

 especially the "South beach." I was quite amused at Day- 

 tona to hear the popular name of "coquina" applied to this 

 shell, and one young man talking about "coquina bouillon." 

 While this is entirely proper, as the Spanish word coquina 

 means, broadly speaking, shell-fish, the name has become so 

 generally used for the shell-rock (often made up largely of this 

 species) that at first it sounded like pretty hard diet. I am 

 sorry that opportunity did not permit my getting a large series 

 of this species including the young, as I should have liked to 

 have made some comparisons of the young of D. variabilis with 

 that of the typical or more northern D. fossor Say. As I re- 

 member I could never satisfactorily separate the two forms at 

 St. Augustine and omitted the latter from my list, although it 

 is recorded from the entire coast of Florida and westward to 

 Texas. Mazyck in his "Catalog of Mollusca of South Caro- 

 lina," says of D. fossor, "very rare, Sullivan Island." 



1 An Annotated List of the Shells of St. Augustine, Florida, THE NAUTI- 

 LUS, vol. iii, pp. 103, 114 and 137, vol. iv, pp. 4-6. 



