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A starch gel electrophoretic survey of testis-specific histones in frogs, snakes and lizards reveals a multiple banded pattern in most of these vertebrates whether the proteins are extracted from the testis cell suspension of a single animal or from chromatin pooled from the testes of several animals. Hence, the multiple banded pattern is probably typical for each individual in a particular species. When such testis-specific histones of Anura are compared with those of Squamata, a notable difference emerges. Thus, the principal Xenopus, Bufo and Rana testicular proteins show entirely different patterns from each other upon starch gel electrophoresis while in Squamata, each of the species examined shows a similar 2-banded pattern in the protamine region of the electrophoretogram. In the anurans Xenopus and Scaphiopus, the testis-specific histone patterns are different even amongst several congeneric species. Although the present survey examines only a limited number of species, the electrophoretic data do point to the order Squamata as one place in vertebrate phylogeny where the diversity of testis-specific histones in fish and amphibians appears to give way to a relative constancy of such proteins in reptiles. Such an evolutionary trend may be consistent with a modified version of Bloch's ('69) hypothesis that relates sperm histone determination. What is the origin and biological significance of such diversity in the sperm histones of fish and amphibians? When does the relative conservation of sperm histone type first occur in vertebrate phylogeny? These questions are especially pertinent in light of recent evidence that many of the somatic histones, especially the arginine-rich ones, are highly conserved in evolution and complex with each

The key to short-term enteral feeding in patients with gastroparesis is to deliver the nutrition beyond the pylorus. Endoscopic assisted methods allow the precise placement of the feeding tube to the small bowel. However, the main difficulty in association with these procedures is feeding-tube migration into the stomach during the withdrawal of the endoscope. We have developed an endoscopic method with a high success rate which prevents this problem. A reusable angiocatheter guidewire was threaded through the feeding tube, passing beyond the distal opening prior to the withdrawal of the scope. Counterpressure was applied to the feeding tube during the withdrawal of the endoscope. We have successfully placed feeding tubes in 22 out of 23 patients with no complications.