(1) Segmentation of dendritic crystals may need to be considered as a new nucleation mechanism in some magmatic systems, especially the systems that experienced a rapid cooling. Segmented dendritic crystals may serve as growth centers around which the crystals grow, like conventional nuclei.

(2) Grain- or phase-boundary migration can change the geometry of boundaries such that older crystals appear younger. Caution must be exercised when inferring the order of crystallization after examining the geometry of crystal boundaries.

(3) Textural metamorphism in igneous rocks may start while the melt is present. This will make it difficult to interpret the textures in igneous rocks, and raises a question, "What is the proportion of primary melt-grown textures in igneous rocks?"

(4) During melt-present deformation of analog material, processes of crystal plastic deformation, dynamic recrystallization, contact melting/redeposition, and sliding along crystal boundaries, operate at the crystal scale, while deformation processes of filter pressing, grain flow, and localized deformation along micro shear zones, operate at the framework scale.

(5) When crystals deform by crystal plasticity during melt-present deformation, the resulting microstructural characteristics will be similar to those formed by solid-state crystal plastic deformation. If deformation ceased before complete crystallization, microstructures such as deformed crystals surrounded by undeformed minerals of igneous textures may be found.

(6) Where contact melting was a major deformation process, the resulting igneous rock may look optically strain-free. However, the presence of microstructural features such as preferred orientation of indented boundaries may indicate the deformation process of contact melting.

(7) Complete removal of melt by filter processing may be possible in igneous rocks by combined processes of crystal plastic deformation, contact melting, and crystal boundary sliding. Adcumulus may be formed by filter pressing in a crystallizing magma chamber where only one phase is saturated.

(8) Grain flow at a low melt fraction can form a preferred orientation of grain long axis. Thus, preferred orientation of igneous minerals may not always indicate high-melt fraction suspension type flow.

(9) When a solid framework deforms with localization along micro shear zones, recognition of the deformation process may be impossible. However, when such zones draw melt in or expel melt, it may be possible to recognize the localized deformation since these zones will have slightly different igneous mineral assemblages.

(10) It is observed from analog experiments that some deformation processes leave no signatures of deformation. Thus, estimation of deformation in igneous rocks, based on presence of crystal plastic deformation microstructures as in rocks deformed at solid state, may not be reliable.
 

ACKNOWLEDGMENTS
It has been my great pleasure to work and have numerous discussion sessions with Professor W.D. Means.  I wish to thank my teacher for his support, encouragement and interest while this work was done at SUNY at Albany.  I also wish to thank Mark Jessell, Paul Bons and Janos Urai for improving this manuscript and making this volume possible.  This work was supported by NSF grants EAR-9017478, EAR-9204781 (equipment) & EAR-9404872 to W.D. Means.