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In a study of sterility in the strawberry begun by the writer in 1914, a portion of the work was directed toward determining the underlying factors causing "nubbins" or imperfectly developed berries. These are commonly produced from the tertiary and later flowers of the inflorescence of many cultivated varieties of strawberry and result in considerable loss of fruit toward the close of the picking season.A study of the fruiting habit of the wild American strawberries mid of the cultivated varieties proves conclusively that the production of nubbins is directly related to pistil sterility, and that pistil sterility is decidedly more prevalent on plants with certain flower types than on others (7). Therefore, since the question of fruitfulness in the strawberry is primarily one of sex, a thorough knowledge of the flower types and of their inheritance is essential to the strawberry breeder if his work is to be other than blind crossing and selecting for chance high-yielding clones.The work on the inheritance of flower types in the strawberry has been discontinued by the writer, but, as some facts have been determined, he presents the data obtained and the conclusions drawn from them. FLOWER TYPES IN THE STRAWBERRYIn the cultivated strawberry, pistillate and perfect flowers are commonly encountered. The pistillate flowers bear small abortive stamens which have never been observed by the writer to produce pollen. The pistils are generally very fertile, producing perfect fruits from most of'the flowers and comparatively few nubbins. The perfect-flowered varieties develop anthers which produce varying amounts of normal pollen. As a class, these varieties are less fertile than the pistillate varieties and produce a higher percentage of nubbins and of sterile or male flowers (7).The wild species of American strawberries may be divided into two types: those which bear only perfect flowers, as Fragaria americana, and those which are dioecious. The pistils of the former species are very fertile, and nubbins or sterile flowers are seldom seen. The dioecious types produce pistillate plants and plants which apparently are hermaphrodites but are in fact staminates. The pistils of the pistillate clones are usually fertile, but the pistils of the staminate clones are rarely so, and the few berries

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In conlnection with the tobacco breeding program at the Kentucky Agricultural Experiment Station, a large number of varieties of tobacco are available, of which a part of the genetic constitution is known. An investigation was made of the chlorophyll a and b and carotene contents of eighteen of these varieties.The method of inheritance of the white burley character has been studied by HENIKA (2). He found that duplicate recessive genes were responsible for this lighter colored type of tobacco but did niot conduct any chemical analyses to show the difference between types. Our purpose was to find out the differences in pigment content of the burley and dark tobaccos and the difference, if any, in the pigment content of mosaic-susceptible and mosaicresistant varieties.Methods MATERIAL USED Seed from 7 dark and 11 burley tobacco varieties were planted on March 2, 1942. The seedlings were all transplanted from the seed bed to individual pots and from the pots to a ground bench in the greenhouse. The plants were grown under similar environmental conditions and were in bloom but had not been topped when the samples were taken, July 13 to 31, 1942. Duplicate samples of two leaves each were taken from a plant. The four leaves came from the lower half of the plant at a height of approximately 1.5 ft. from the ground and were consecutive leaves on the stalk. The length and width of the leaves were measured to the nearest cenitimeter and then the midribs were removed. The right half of one leaf and the left half of the other leaf of each sample were analyzed; the other half of each leaf was used for moisture percentage determination. The moisture sample was dried in an oven at 650 C. for 48 hours or longer. The percentag,e dry weight of the sample analyzed was assumed to be the same as that of the moisture sample.YOUNG and JEFFREY (4) found that there was a high degree of correlation between the product of length and width and the leaf area. Their equation was used in determining leaf area. Since the equation used was developed for Ky. 16, the calculated leaf area of those varieties which have a different shape of leaf may be inaccurate. This is particularly true of the species Nicotiana digltta (F3 Ky. 5 x N. gluttinosa) which has a petiolate leaf. The calculated area of leaves of this strain is probably too great, resulting in chlorophyll and carotene values which are too low when expressed on an area basis.

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