The burrow extends into the rock for quite some distance and may turn in 



various directions before the bottom — some four or six inches away is 



reached. This adds to the difficuhy of removing the moHusk undamaged, 

 as the collector is never sure as to just where the shell lies. Many specimens 

 are shattered. 



With Gastrochaena rostrata, the cylinders emerge from the rock, side 

 by side, at that point the tubes turn and the openings point in opposite 

 directions and are horizontal instead of vertical as in the other two. The 

 burrow of G. rostrata lies but a short distance beneath the surface of the 

 rock and the shell is not nearly so difficult to remove as the others. This 

 is fortunate as it is the rarest of the Florida Gastrochaenidae. 



There is no difficulty in locating the burrows of Rupellaria typica or 

 Petricola lapicida, as they lie close to the surface of the rock. Usually the 

 black tips of the siphons are visible and resemble a colon punctuation mark. 



Most collectors of the rock dwellers try to preserve a portion of the 

 rock at the entrance of the burrow to accompany the shell in the cabinet, 

 thus adding interest to the specimen. With Lithophaga, this is not a difficult 

 matter, but fully one half of the Gastrochaena cylinders are broken while 

 removing the shell. 



Coralliophaga coralliophaga is frequently found in a Lithophaga bur- 

 row. During several winters spent in shell collecting among the Florida 

 Keys I have taken alive the following species: Lithophaga antillarum 

 d'Orbigny, L. hisulcata d'Orbigny, L. nigra d'Orbigny, L. aristata Dillwyn, 

 Botula fusca Gmelin, Gastrochaena cuneiformi's Spengler, Rupellaria typica 

 Jonas, Petricola lapicida Gmelin, Coralliophaga coralliophaga Gmelin, and 

 Fundella candeana d'Orbigny. 



Bilge Pump. When the ocean floor is of rock that is more or less 

 honeycombed, and with small pot holes, it is surprising what fine specimens 

 of the small varieties may be obtained by the use of a common bilge pump 

 which is standard equipment in small boats. The end of the pump is 

 placed in a sand-filled pocket in the rock; the sand as well as the mollusks 

 that have taken refuge in the hole are pumped with the water into a 

 screen; the sand and water flow through, leaving the specimens all ready 

 for the collector. 



Sieve. A handy device often used consists of a small round sieve which 

 has been attached to a long handle. They are easily made from a 5 or 6 

 inch gravy strainer to be had at most ten cent stores. They have two bent 

 prongs in front which must be bent backward so as not to interfere with 

 the use of the net. No device equals this when working in waist or chest 

 deep water. 



Rust. Freshly taken specimens should never be placed, even tempo- 

 rarily, in a rusty metal container or in contact with rusty chains or 

 other rusty objects for it is remarkable how soon they will become rust 

 stained, and it is almost impossible to remove this stain. 



(4) 



