Adv. mar. Biol., Vol. 5, 1970, pp. 307-436
SCATOLOGICAL STUDIES OF THE BlVALVlA
(M 0 LLU SCA)
KOHMAN Y. ARAKAWA
Hiroshima Fisheries Experimental Xtation
Ondo, Aki-gun, Hiroshima, Japan
I. Introduction
. ,
..
..
..
.. . . . .
11. Material and Techniques
. .
..
. . . . . .
111. Morphology
. . . . .. . . .. . . . .
A. Classification of Faecal Pellets . . . .
..
..
B. Definition of Pellet-types
. .
. .
. .
..
C. Descriptions of Faecal Pellets . . . .
. .
..
I. Protobranchia (Gastroproteia) . .
..
. .
11. Septibranchia (Gastrodeuteia) . .
..
..
111. Gastrotriteia
. .
. .
..
. .
..
IV. Gastrotetartika . .
. .
. . . .
..
V. Gastropempta
. .
..
. .
..
..
IV. Biological Significance of the Characteristic Form of Faecal Pellets
. . 379
Life of the Animals . . . .
.. .. . . .. . . 379
the Digestive Organs
. .
. .
. .
. .
. . . . 381
V. Use of Faecal Pellets as a Systematic Index
. .
. . . .
. . 403
VI. Evolutionary Trends of Faecal Pellets
. .
. .
..
. .
. . 405
VII. Biodeposition of Suspension Feeding Bivalves
. . .. .. .. 413
A. Factors Influencing Biodeposition
. .
..
. .
* .
.. 419
B. Daily and Seasonal Aspects of Biodeposition , . .. .. . . 421
C. Effects of Biodeposition upon Various Marine Environmental
.. ..
..
..
_ . 425
VIII. Bibliography
. .
. .
..
. .
.. . .
. . ..
. . 429
. .
. .
.. .. . . . . facing page 436
A. Relation of Faecal Characteristics to the Feeding Habit and Mode of
B. Relation of Faecal Characteristics to the Structure and Function of
Conditions . . .. ..
IX. Plates
. . ..
.. . . 307
.. . . 309
..
. . 310
.. .. 310
* .
.. 310
. .
. . 317
..
.. 317
..
. . 320
* .
. . 320
..
. . 334
. .
. . 345
I. INTRODUCTION
Since H. B. Moore’s pioneer work on bivalve faecal pellets (1931,
1931a, 1931b and 1933), valuable additions to our knowledge on the
subject have been made from various angles by many workers (Edge,
1934; Schafer, 1953; Manning and Kumpf, 1959; Haven and MoralesAlamo, 1966 ; Ota, 1959; Ota and Fukushima, 1961 ; and Arakawa, 1963,
1965, 1968). Although suggestions have been made about the practical
value of the study of faecal pellets in geology, sedimentology, palaeoecology, systematics, marine ecology etc., basic knowledge about bivalve
faecal pellets remains scrappy and superficial and no worker has yet given
a full and systematic account of them. The present work was designed
first to review and enlarge our scanty knowledge on the structure of
bivalve faeces and to suggest possible biological interpretations of the
307
SCATOLOGICAL STUDIES OF THE BlVALVlA
(M 0 LLU SCA)
KOHMAN Y. ARAKAWA
Hiroshima Fisheries Experimental Xtation
Ondo, Aki-gun, Hiroshima, Japan
I. Introduction
. ,
..
..
..
.. . . . .
11. Material and Techniques
. .
..
. . . . . .
111. Morphology
. . . . .. . . .. . . . .
A. Classification of Faecal Pellets . . . .
..
..
B. Definition of Pellet-types
. .
. .
. .
..
C. Descriptions of Faecal Pellets . . . .
. .
..
I. Protobranchia (Gastroproteia) . .
..
. .
11. Septibranchia (Gastrodeuteia) . .
..
..
111. Gastrotriteia
. .
. .
..
. .
..
IV. Gastrotetartika . .
. .
. . . .
..
V. Gastropempta
. .
..
. .
..
..
IV. Biological Significance of the Characteristic Form of Faecal Pellets
. . 379
Life of the Animals . . . .
.. .. . . .. . . 379
the Digestive Organs
. .
. .
. .
. .
. . . . 381
V. Use of Faecal Pellets as a Systematic Index
. .
. . . .
. . 403
VI. Evolutionary Trends of Faecal Pellets
. .
. .
..
. .
. . 405
VII. Biodeposition of Suspension Feeding Bivalves
. . .. .. .. 413
A. Factors Influencing Biodeposition
. .
..
. .
* .
.. 419
B. Daily and Seasonal Aspects of Biodeposition , . .. .. . . 421
C. Effects of Biodeposition upon Various Marine Environmental
.. ..
..
..
_ . 425
VIII. Bibliography
. .
. .
..
. .
.. . .
. . ..
. . 429
. .
. .
.. .. . . . . facing page 436
A. Relation of Faecal Characteristics to the Feeding Habit and Mode of
B. Relation of Faecal Characteristics to the Structure and Function of
Conditions . . .. ..
IX. Plates
. . ..
.. . . 307
.. . . 309
..
. . 310
.. .. 310
* .
.. 310
. .
. . 317
..
.. 317
..
. . 320
* .
. . 320
..
. . 334
. .
. . 345
I. INTRODUCTION
Since H. B. Moore’s pioneer work on bivalve faecal pellets (1931,
1931a, 1931b and 1933), valuable additions to our knowledge on the
subject have been made from various angles by many workers (Edge,
1934; Schafer, 1953; Manning and Kumpf, 1959; Haven and MoralesAlamo, 1966 ; Ota, 1959; Ota and Fukushima, 1961 ; and Arakawa, 1963,
1965, 1968). Although suggestions have been made about the practical
value of the study of faecal pellets in geology, sedimentology, palaeoecology, systematics, marine ecology etc., basic knowledge about bivalve
faecal pellets remains scrappy and superficial and no worker has yet given
a full and systematic account of them. The present work was designed
first to review and enlarge our scanty knowledge on the structure of
bivalve faeces and to suggest possible biological interpretations of the
307