The cochlear nuclear complex was investigated in snakes of the advanced family Colubridae and the primitive family Boidae. This study was undertaken in an attempt to correlate the elaboration of the cochlear nuclei with behavior and phylogeny and to elucidate the relative effects of these factors on the evolution of the cochlear nuclear complex. Fifty-five brains, of 14 colubrid species and three boid species, were examined to collect data on neuron diameter, neuron population, nuclear volume, and neuronal density of the cochlear nuclear complex and of its component nuclei (nucleus angularis and nucleus magnocellularis). Intraspecific and interspecific comparisons of the data were performed by nested analysis of variance. The species were grouped by cluster analysis and ranked on the basis of the morphometric parameters. Interspecific comparisons indicate that the elaboration of the cochlear nuclei is related, first, to prey preference and, second, to habitat preference. The most elaborate cochlear nuclei occur in species with a preference for vertebrate prey. Burrowing species that prey on vertebrates exhibit the highest degree of elaboration of the cochlear nuclei. In some burrowing species, the nucleus magnocellularis is differentiated into medial and lateral subdivisions. The primitive boid snakes show greater elaboration of the cochlear nuclei than do most of the advanced colubrid snakes. The elaboration of the cochlear nuclear complex in snakes seems to reflect the influence of both behavior and phylogeny. Further investigation of primitive snakes of varied behaviors is needed to establish more clearly the influence of phylogeny on the evolution of the cochlear nuclear complex.

The auditory and vestibular projectionsof the posterior ramus of the statoacoustic nerve were traced using silver degeneration techniques in the tegu lizard, Tupinambis nigropunctatus. Four tegus were perfused 7, 14, 21, and 28 days after labyrinthectomy, and three were perfused 21 days after cochlear ductectomy; 21 days was found to provide optimal degeneration patterns. Both surgical procedures destroyed the intraotic ganglion of the posterior ramus, which innervates the posterior crista, basilar papilla, macula lagena, macula sacculus, and possibly the macula neglecta. The vestibular components of the posterior ramus project to the medioventral part of the dorsolateral nucleus, the dorsal and dorsomedial parts of the ventrolateral nucleus, the dorsal part of the descending nucleus, and throughout the dorsomedial nucleus. No direct vestibulocerebellar tract is associated with the intraotic ganglion. The auditory components of the posterior ramus project to the entire nucleus angularis and nucleus magnocellularis. The nucleus laminaris receives either no primary statoacoustic fibers or very sparse projections on its lateral border.

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I propose three guided questions for reflection as a jumpstart organizational formula for students with poor writing application skills to follow when responding to an open-ended question. The recipe prescribes that the student (1) understand the question design, (2) identify the intent or objective of the question, and (3) proceed to identify the key words or phrases that are relevant to answer the question. The three prompts serve as a "getting started" writing template for students to organize their thoughts and then compose the introductory sentences of their answer. The identified significant words and phrases should then be further explained and clarified by the student to complete the main body of the response. In addition, these opening sentences serve as an index at the outset of the response for a teacher to gauge the student's understanding of and approach toward answering the question.