Figure 5. — Cross section of a southern quahog shell (M. 

 campechiensis) showing laminated structure. Dark 

 bands (closely spaced laminae) represent annuli that 

 appear as deep depressions on the outer surface of the 

 shell (marked by lines). 



Figure 6. — Largest known southern quahog (M. campechi- 

 ensis) — 172 mm. — collected alive from Boca Ciega Bay, 

 Fla. The shell has been cut transversely to show lami- 

 nated structure from which the age of the clam can be 

 determined. 



characteristic that makes it well suited for 

 aquaculture is its mode of reproduction. Eggs 

 are laid in a jelly mass attached to the bay 

 bottonn where they can be picked up at low 

 tide and transferred to prepared trays of 

 sediment in tanks of running sea water. 

 Preliminary experiments show that at least 

 72 worms with an average length of 15.2 

 cm. can be harvested in 6 months from a 

 15 -cm. layer of sand, 1 m.^. Locally, the 

 worms sell for 50 cents per dozen. At this 

 rate, worm production from one sediment 

 tray is worth $3,00 every 6 months. Feed- 

 ing the worms is no problem, because they 

 consume algal detritus that accumulates inthe 

 tanks. 



The marine baitworm business now depends 

 on blood and clam worms dug along the coasts 

 of New England and Eastern Canada. These 

 worms are hard to rear because they spawn 

 into the sea and produce planktonic larvae 

 that are difficult to obtain and feed. We 

 believe that the culture of lugworms can be 

 a profitable business capable of increasing 

 the income from marine bait worms (now 

 valued at about $1.3 million annually). 



Squid 



Biological collections in Tampa Bay in 

 1961 and 1962 showed that the squid ( Lolli- 

 guncula brevis ) occurs throughout the Bay, 

 especially in the brackish waters of Old 

 Tampa Bay, Hillsborough Bay, and upper 

 Tampa Bay. In 1968, egg masses of L. brevis 

 were found in Tampa Bay in February and 

 April. These finds are of interest because 

 the embryological development of L. brevis 

 has never been described. Embryos were 

 maintained in the laboratory, and a develop- 

 mental series for further study was photo- 

 graphed and preserved. Gross anatomical 

 features of the embryonic squid are clearly 

 visible through the clear matrix of the egg 

 mass and egg (fig. 7). 



Sea Grass 



We started a cooperative project with the 

 BCF Technological Laboratory in College 

 Park, Md., inthe summer of 1967 todetermine 

 the nutritional value of a sea grass known 

 as turtle grass ( Thalassia testudinum ). Turtle 

 grass is the most common sea grass in Tampa 

 Bay and in shallow water along the west 

 coast of Florida. Grass beds harbor a rich 

 assemblage of marine life and produce enor- 

 mous amounts of organic matter. In the past, 

 biologists have successfully used leaves of 

 turtle grass as a mulch and fertilizer on 

 an experimental basis for crops such as 

 tomatoes and strawberries. 



