Biology of Bryozoans

List of Contributors

Preface


1 Gametogenesis of Bryozoans

I. Morphology of the Ova and Oogenesis

II. Morphology of the Spermatozoon and Spermiogenesis

References


2 Brooding Patterns of Bryozoans

I. Introduction

II. Gymnolaemata

III. Stenolaemata

IV. Phylactolaemata

V. Summarizing Comments on Brooding

VI. Breeding Seasons

References


3 Structure and Classification of Gymnolaemate Larvae

I. Introduction

II. Larval Structure

III. Larval Types

IV Conclusions

References


4 Metamorphosis, Ancestrulae, and Coloniality in Bryozoan Life Cycles

I. Introduction

II. Gymnolaemata

III. Cyclostomata

IV. Phylactolaemata

V. Summary

References


5 Ultrastructure, Mineralogy, and Development of Bryozoan Skeletons

I. Introduction

II. Interpretation and Application of Skeletal Ultrastructure

III . Stenolaemate Bryozoa

IV. Cheilostome Bryozoa

References


6 Polymorphism

I. Some Elementary Definitions

II. Distribution of Polymorphism among Bryozoans

III. Types of Polymorphs: Generalities

IV. Active Defense: Avicularia and Vibracula

V. Cleaning: Nanozooids

VI. Passive Defense: Spinozooids

VII. Colony Strengthening: Intercalated and Marginal Kenozooids

VIII. Colony Support: Rhizozooids, Stylozooids, and Stolons (?)

IX. Survival of Unfavorable Conditions: Rhizozooids and Stolons, Hibernacula, Statoblasts, and Sacculi

X. Interzooidal Connections: Interzooids

XI. Sexual Reproduction: Gonozooids

XII. From Free to Sedentary Life: Ancestrulae

XIII. Induction and Origin of Polymorphism: Generalities

XIV. The Individual Concept

XV. Ontogenetic Development of Polymorphs

XVI. Substitution of Different Polymorphs

XVII. Conditions Inducing Polymorphism

XVIII. Origin and Evolution of Polymorphism

References


7 Feeding in Marine Bryozoans

I. Introduction

II. Review of Functional Morphology of Feeding

III . Variation in the Bryozoan Polypide

IV. Bryozoan Feeding and Culture

V. General Discussion

VI. Suggestions for Future Research

VII. Conclusions

References


8 Experimental Techniques and Culture Methods

I. Introduction

II. Experimental Work in the Field

III. Simple Rearing in the Laboratory

IV. General Conditions for Laboratory Work

V. Cultivation or Long-Term Rearing

References


9 Interzooecial Communications and the Funicular System

I. Introduction

II. Case of the Phylactolaemates

III. Case of Eurystome Gymnolaemates

IV. Case of Cyclostome Gymnolaemates

V. Conclusions

References


10 The Aging Process in Bryozoans

I. Introduction

II. General Features

III. Ultrastructural Features of Regression

IV. The Fate of the Brown Body

V. Distribution of Cyclic Regression and Regeneration

VI. Cause and Effect of Brown Body Formation

VII. Summary

References


11 The Bryozoan Nervous System

I. Introduction

II. General Anatomy

III. The Interzooidal Information Hypothesis

IV. Discussion

V. Summary

References


12 Taxes and Tropisms of Bryozoans

I. Introduction

II. Orientation Responses of Free-Swimming Larvae and Motile Colonies

III. Orientation Responses of Settling Larvae

IV. Orientation Responses of Fixed Colonies

V. Summary

References


13 Fouling and Bioadhesion: Life Strategies of Bryozoans

I. Introduction

II. Reproductive Strategies

III. Bioadhesives and Attachment

IV. Fouling Communities

V. Fouling Colonial Strategies

References


14 Population Genetics of Bryozoans

I. Introduction

II. Population Size

III. Outbreeding and Inbreeding

IV. Linkage

V. Geographic Variation

VI. Genetic Variability

VII. Implications for Speciation

VIII. Appendix: Summary of Techniques

IX. Addendum

References


15 An Adaptive Model for the Evolution of the Ectoproct Life Cycle

I. Introduction

II. The Ground Plan Concept and Its Bearing on the Origin of Phyla

III. The Position of the Ectoprocta in Lophophorate Phylogeny

IV. General Features of the Phoronida and Ectoprocta

V. The Adaptive Basis of Morphological Differences in the Adult Stage of Phoronids and Ectoprocts

VI. A Model for the Origin of the Adult Features of the Ectoproct Ground Plan

VII. Historical Evidence Bearing on the Model

VIII. The Viability of Intermediate Modes of Life

IX. Evolution of the Larval Stage of the Life Cycle

X. The Actinotroch Larva of the Phoronida

XI. Larval Development in the Ectoprocta

XII. The Cyphonautes Larva

XIII. Discussion and Conclusions

References


16 Phylogenetic Considerations: The Protostomian Relationships

I. Introduction

II. The Relationship between Entoprocts and Ectoprocts

III. Discussion of Possible Relationships with the Phoronids

IV. The Relationships of the Bryozoans (Entoprocts + Ectoprocts)

References

Appendix

Index