196 



Brown, F. A., Jr., M. F. Bennett, H. M. Webb, and C. L. Ralph. 1955. 



A correlation between barometric pressure changes and oyster and quahog 

 activity. Anat. Rec. 122(3): 462-463. 



Forms of mean daily cycles of barometric pressure and mean daily cycles of 

 opening and closing of shells in constant light and temp were compared for 

 7 two-week periods. General forms for the 2 cycles were quite striking, but 

 forms of cycles for certain portions of the day were often inverted relative 

 to the same portions for other 2-week periods. Activity cycles, often 

 having forms paralleling pressure changes, were out of phase with pressure 

 changes by 1 to 3 hrs , suggesting a correlation between rate and direction 

 of pressure change and amount of clam activity. An hourly correlation for 

 all data between minutes open/hr and concurrent rate and direction of 

 pressure change showed increased activity in proportion to rate of pressure 

 fall and decreased activity in proportion to rate of rise. It was suggested 

 that the character of the response related to any given barometric pressure 

 was determined in some way by an endogenous rhythmic process. (Abstracter's 

 note: It apparently is the policy of Anat. Rec. not to include illustrations. 

 This note would have been easier to understand if graphs had been included.) 



- J.L.M. 



197 



Brown, Frank A., Jr., M. F. Bennett, H. M. Webb, and C. L. Ralph. 1956. 



Persistent daily, monthly and 27-day cycles of activity in the oyster and 

 quahog. J. Exp. Zool. 131(2): 235—262. 



Venus meraenavia used in experiments were collected at West Falmouth, Mass. 

 and held in the laboratory under continuous illumination of about 1 ft.c. 

 Experiments were carried out from 17 June to 30 Aug. 1954, at room temp, 

 which varied between 21 and 27°C. No overt rhythm of opening and closing 

 was observed, but statistical rhythms were detected. A low degree of 

 opening was seen about 6 am and a relatively high degree through the rest 

 of the day, with a tendency for maxima in late morning and late afternoon 

 or early evening. Daily cycles of opening and closing appeared to be 

 correlated with barometric pressure changes. The characteristic pattern 

 was repeated at 27-day intervals, and it was postulated that this was in 

 some way related to the 27-day cycle of rotation of the sun on its axis. 



- from authors' summary - J.L.M. 



198 



Brown, F. A., Jr., H. M. Webb, M. F. Bennett, and M. I. Sandeen. 1955. 



Evidence for an exogenous contribution to persistent diurnal and lunar 

 rhythmicity under so-called constant conditions. Biol. Bull. 109(2): 238-254, 



199 



Brown, Robert S.,and Carole J. O'Toole. 1978. 



Histochemical analyses of pigment accumulations in Meraenavia meraenaria L. 

 and Mya arenaria L. Proc . Natl. Shellf. Assn. 68: 75-76 (abstract). 



Histopathologic analysis of Meraenavia collected from Massachusetts, Rhode 

 Island, and New Jersey demonstrated accumulation of pigments of 3 types: 

 1) irregular, 2-20 pm diam, orange-brown staining bodies, present extra- 

 cellular ly in alimentary tract epithelium and gonadal connective tissue, and 

 intracellularly in renal epithelium; 2) spherical 7-12 pm diam eosinophilic 

 concretions, present intracellularly in renal epithelium; and 3) 30-200 ym 

 diam melanotic casts present in renal tubular lumens. Only type 1 pigment 

 was found in My a. This pigment had morphological characteristics of lipo- 

 fuscins (brown staining bodies of oxidized lipids) found in vertebrates. 

 All 3 pigment types had histochemical characteristics of lipofuscins. Ac- 

 cumulation of these pigments appears to be a normal physiological process 

 although abnormally large accumulations were noted in clams from certain 

 environments. - J.L.M. 



55 



