1917] FOODS — HUMAN NUTRITION. 261 



cation is when the largest larvae are about half grown and when the holes in 

 the leaves are not larger than 0.5 in. in diameter. At this time nearly all the 

 eggs have hatched." 



Some American Hymenoptera, J. C. Crawford {Proc. Ent. Soc. Wash., 18 

 (1916), No. 2, pp. 127, 128). 



The citrus mite named and described for the first time, E. A. McGregor 

 (Aim. Ent. Soc. Amcr., 9 (1916), No. 3, pp. 284-290, figs. 13).— The citrus mite, 

 formerly considered identical with Penthalodes m-ytilaspidis, is here described 

 from material taken on lemon leaves at Orlando, Fla., as Tctranyclms citri 

 n. sp. It was introduced into California from Florida on nursery stock about 

 1890, and is doubtless the most injurious red .spider found on citrus trees on 

 the Pacific coast. It is severest as a pest of sweet orange in California, whereas 

 in Florida it all but forsakes the sweet orange, and is severe only upon lemon, 

 sour orange, and grapefruit. The citrus red spider on orange in California 

 produces a silvering, dwarfing, and dropping of the fruit, and also causes dis- 

 coloration and dropping of the foliage. 



A new mite from the Hawaiian Islands, P. J. O'Gara (Science, n. ser., 44 

 (1916), No. 1126, p. 142). — The author records observations of injury to the 

 Chinese litchi tree (Litchi chinensis), growing on the grounds of the Federal 

 Experiment Station at Honolulu, by a mite which is apparently a new species 

 of Eriophyes. 



The dispersal of leaf -blister mite of cotton, (Agr. News [Barbados], 15 

 (1916), No. 368, p. 186). — Data are presented which indicate that the leaf -blister 

 mite of cotton can be introduced in the seed. Observations have also shown 

 that the full-grown mites have a tendency to ascend to the tips of leaf hairs 

 and assume what appears to be a waiting position, the first pair of legs being 

 extended and with which they attach to any moving object that comes in con- 

 tact with them. It is suggested that leaf-blister mites would in this way attach 

 to insects and birds and be disseminated by them. 



FOODS— HITMAN NUTRITION. 



On the use of certain yeast nutriments in bread making, R. A. Kohman, 

 C. Hoffman, T. IM. Godfrey, L. H. Ashe, and A. E. Blake (Jour. Indus, and 

 Engin. Chem., 8 (1916), No. 9, pp. 781-789, figs. 3). — Experiments here reported 

 were carried out to determine the effect of certain mineral salts, such as are 

 commonly found in natural waters, upon the fermentative activity of the yeast 

 and also upon the quantity of yeast necessary for leavening purposes. The 

 mineral substances present in flour, milk, yeast, and other raw materials used 

 in bread making were also studied. The following conclusions are drawn : 



" By the use of minute quantities of ammonium and calcium salts and potas- 

 sium bromate in bread, from 50 to 65 per cent of the usual amount of yeast 

 can be saved. Incident to the economy in yeast thus effected, there is a saving 

 of about 2 per cent of fermentable carbohydrates, calculated upon the total 

 flour used, due to the greatly diminished consumption of these by the yeast. 



"The proper use of nutrient salts for the yeast gives greater control over 

 the dough batches and aids in the production of better and more uniform bread, 

 regardless of the locality. The added salts conserve the inherent qualities of 

 the dough and consequently maintain its stability and strength to a far greater 

 degree than by the old process. The finished loaves are improved in quality, 

 flavor, texture, bloom, and uniformity." 



A cause of mustiness in bread, A. M. Wright (Jour. Soc. Chem. Indus., 35 

 (1916), No. 20, pp. 1045, 1046). — Examination for micro-organisms of flour 

 alleged to have been the cause of mustiness, observed in bread baked from it, 

 showed the presence of Rhizopus nigricans and Aspergillus. 



