EAST COAST MARINE SHELLS 



125 



example on PI. 40. 



Easily recognizable on account of 

 the left-handed shell. 



PI. 49, Fig. 7 



PI. 40, Fig. 18 (Dextral) 



PI. 48, Fig. 4 



Cape Hatteras, North Carolina to 



Cuba 



BUSYCON PYRDM Dillwyn. Shell with deeply 

 channelled sutures, no tubercles or spin- 

 ous processes; ornamented with inconspicu- 

 ous ribs or striae; epidermis hairy; color 

 a yellowish rust inside and out. Length 

 3-4 inches. It lives in shallow water, 

 usually on sand. 



PI. 42, Fig. 12 



Cape Hatteras to Gulf of Mexico 



GENUS MELONGENA Schumacher 1817; 

 Galeodes Roeding 



Shell solid, spire short, spiny; 

 canal short; outer lip simple; operculum 

 claw-like, nucleus apical. 



MELONGENA CORONA Gmelln, The spines which 

 crown this species are gracefully arranged, 

 often in double or triple series. It is an 

 abundant shallow water shell, often living 

 in and covered with mud. Length of typical 

 shell S-5 inches. 



The range westward is doubtful. 

 Authentic records from Alabama to Texas are 

 desired. 



PI. 47, Fig. 2 



PI, 48, Fig. 1 



PI. 58, Figs. ?, 8 



Indian River region; Florida; 



Florida Keys; west coast of Florida 



The varieties recently reviewed and 

 described by Pilsbry in "The Nautilus" are 

 ecologic and not true races. For conven- 

 ience they may be arranged as follows: 



MELONGENA CORONA ALTISPIRA Pilsbry. An ex- 

 tremely long, narrow form. The diameter is 

 about one-half the length or less. Length 

 71 mm., diameter 31 mm. 



This form lives near the northern 

 limit of the species on the Florida east 

 coast. 



PI. 58, Fig. 4 



Oceanus, Brevard County to Mate- 



cumbe Key, Florida; west coast of 



Florida 



MELONGENA CORONA INSPINATA Richards, Spines 

 on edges of square shoulders entirely ab- 

 sent; no traces of knobs in place of the 

 spines; a few (six to eight) sub-basal 

 spines present. 



Specimens have been collected at 

 Sarasota and Terra Ceia, Florida. 



PI. 47, Fig. 7 



Florida west coast 



MELONGENA CORONA MINOR Sowerby. The dwarf 

 form, 2 inches long more or less, which 

 lives in great profusion upon mud flats. 

 Like the typical it may have few spines in 

 a circle at base or spines at shoulder 

 alone. In the Indian River region it has 

 the tendency to become longer, being near- 

 er the form altispira. 



PI. 58, Fig. 9 



Florida 



MELONGENA CORONA PERSPINOSA Pilsbry. Large, 

 heavy, wider than corona; shoulder spines 

 projecting at right angles and doubled or 

 tripled by accessory spines below the regu- 

 lar series; lower series of spines invari- 

 ably well developed. The example figured 

 by Pilsbry measured 109 mm. in length. 



PI. 58, Fig. 6 



Tampa Bay south to Marco Pass and 



Lossmans Key 



MELONGENA CORONA SUBCORONATA Heilprin. 

 Shell wider and shorter than corona; strong 

 shoulder spines extending at right angles 

 and with basal series always present. PI. 

 58, Fig. 7 represents a form near this. 



Found fossil in the Caloosahatchie 

 River Pliocene beds. 



PI. 28, Fig. 4 



PI. 58, Fig. 7 



Florida (Pliocene) 



MELONGENA MELONGENA Linne. Differs from 

 M. corona in the possession of a distinct 

 groove close to the suture. There are from 

 one to three rows of spines on upper por- 

 tion of body whorl and an additional row' be- 

 low. Length 3-5 inches. 

 PI. 48, Fig. 5 

 Florida Keys; West Indies 



