Miscellaneous. 223 



of Mistletoe upon the growth of the twigs below it is to be ascribed 

 partly to the aborted condition of the terminal shoots, and partly to 

 the fact that the juices assimilated by the Mistletoe are chiefly ap- 

 plied to its own increase, and may be less fitted for the development 

 of the tree on which it grows. — Bericht der Akad. der Wiss. in Wien, 

 June 30, 1865, p. 113. 



On a Fungus which is developed in Ivory and Bone. 

 By Professor Wedl. 



In examining some sections of human teeth which had been 

 macerated for a few days in water, Professor Wedl found that the 

 cement and the peripheral layers of dentine were furrowed by micro- 

 scopic channels. He soon recognized in these channels small parasitic 

 plants, closely resembling those which perforate the shells of Mol- 

 lusca. A careful examination of the water in which the sections had 

 been macerated furnished numerous small cells, which might be re- 

 garded as the spores of the Fungus. Fragments of normal teeth 

 placed in the same water were soon infested by these little parasites, 

 the operation of which is, however, confined to the cement and 

 dentine, and never extends to the enamel. The Fungus also 

 attacked fragments of bone macerated in the water. 



These little Fungi seem to be developed at the expense partly of 

 the organic and partly of the inorganic matter of the ivory and bone ; 

 and the conditions of their multiplication doubtless frequently occur 

 in nature. They do not, however, appear to attack teeth until 

 after death ; so that they have nothing to do with caries. Pro- 

 fessor Wedl has ascertained that these parasites have been in action 

 from a high antiquity, many teeth of fossil Fishes and Mammalia 

 exhibiting unequivocal traces of their action. — Sitzungsher. Akad. 

 Wiss. in Wien, July 14, 1864; Bibl. Univ. 1865, Bull. Sci. 

 p. 231. 



Note on the Ammobroma Sonorse. 



This (the literal translation of which is " sand food of Sonora") is 

 the name of an extraordinary root-parasitic plant, of the region at 

 the head of the Gulf of California, which Dr. Torrey has just de- 

 scribed and figured in the eighth volume of the 'Annals of the 

 Lyceum of Natural History of New York.' It has been briefly 

 noticed before (but never fully characterized) as a new genus allied 

 to the rare Mexican Corallophyllum of Kunth (or Lennoa, Lexarza), 

 and still more to the Califomian and hardly better known Pholisma 

 of Nuttal. It hardly throws any new light upon the afiinity of 

 these strange plants, which, though justly thought to be rather 

 Monotropaceous than Orobanchaceous, are still obscure. This 

 plant, growing in a forlorn sandy desert, almost covered by the sand 

 in which it lives, was found by its discoverer, the late Col. A. B. Gray, 

 to form a considerable part of the sustenance of the Papigos Indians 

 of the district, and is said to be very luscious when first gathered 

 and cooked, resembling in taste the sweet potato, only far more de- 

 licate. — Sillimah's Journal, July 1865. 



