(Contribution from the lyarine Laboratory, University of Miami) 



RESPIRATION OF TEREDO LiVRVAE 

 by Charles E. Lane 



Previous communications from this laboratory (Lr.ne, Posner & Greenfield, 

 1952, Lasker and Lane 19^3, and Isham and fierney 19!?3) have shown that 

 the free- swimming, infective larval stage of Teredo in locail waters does 

 not significantly exceed seventy-tiro hours in extent. During this time 

 the animals have not been observed to feed. The pre-attachment activities 

 of the animal must be presumed to be powered chiefly by glycogen. This 

 is deposited in the ovum in granular form during oogenesis . Additional 

 glycogen may be contributed to the larva during the time that it is actually 

 embedded in the maternal gill (Lane, Posner & Greenfield loc _cit). At the 

 termination of this transient free-swimming stage the larvae attach them- 

 selves permanently to a vfooden substratum within which they spend the rest 

 of their adult life span. A cellulase enzyme system exists in both larval 

 and adult Teredo (Greenfield and Lane, 195^3). This enzyme complex may con- 

 tribute significantly to the process of penetration of the wood. 



The act of penetration of wood confers upon the larva a degree of immunity 

 to environmental hazards except those in solution — either in the wood 

 itself or in the water which constitutes the respiratory stream. Thus it 

 is that preventive measures, to be effective, must be directed against 

 the larva during the vulnerable first seventy-two hours of its life. 



A sensitive index of physiological condition, or of the effectiveness of 

 sub-lethal concentrations of toxic substances, is provided by the rate of 

 oxygen consumption of living systems. Thus it beccme of interest to de- 

 limit some of the parameters of normal respiration in the free-living, pre- 

 attachment stages of our local Teredo before beginning any study of the 

 effectiveness of toxic materials, it is the purpose of this communication 

 briefly to describe \he methods and some of the results of this study of 

 normal animals. 



The apparatus employed is a capillary microrespirometer, Fig. 1. It con- 

 sists of a pear-shaped chamber blown in one end of 0.^ mm. pyrex capillary 

 tubing. The volume of the chamber varied in different respirometers over 

 the range of six to 12^ microliters (l/iL » 1 mm^). Tlie volume should_be 

 kept as small as possible to increase the stability of the system (Tobias 

 19k3). lit the other end of the capillary tubing is an inside syringe-taper 

 ground joint. This seats in the outer matching ground joint of the thermo- 

 barometer or compensation chamber. This latter portion of the apparatus 

 should be as large as is consistent with ease of manipulation, vfe have 

 generally sought to have its volume 1000 times that of the respirometer 

 chamber. This insures maximum sensitivity of the system. The upper end 

 of the compensation chamber is closed by a stopcock. The entire assembly 

 is immersed in a constant temperature water bath maintained at 25.0OC, 



L - 1 



