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* 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 maclura) is called by the fishermen. 
Donazx 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. JI 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, Tau Navtt- 
Luvs, vol. iii, pp. 103, 114 and 137, vol. iv, pp. 4-6. 
