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Fifty-six compounds from the odor of 'calling', sexually mature, laboratory reared males of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritida~) were isolated by headspace trapping on Tenax columns and identified using GC/MS techniques (69 total compounds were detected). Electroantennogram responses (EAGs) to 54 of the 56 identified compounds as well as 5 analogs were tested on both sexes. Significant differences between the sexes in their responsiveness were found in 9 of the 54 identified compounds tested. There was no correlation between the amplitude of the EAG response and the relative abundance of compound identified from headspace analysis. Of the five 'major' identified components, three elicited relatively small EAG responses, while two elicited large EAGs compared to the hexan-l-ol standard. The relative ranking of EAG responses were: methyl and ethyl hexenoates and hexanoates > C4 -C6 esters and/or acetates > ethyl and methyl octenoates > monoterpenes > sesquiterpenes > C2-C5 acetates, alcohols and ketones. Behavioral bioassays on each of the five 'major' identified components as well as a blend of six of the compounds showed some degree of attractancy to virgin females which in some cases approached the response to a 'pheromonal' standard (male odors absorbed onto filter paper). These results are discussed in relationship to the insect's antennal sensitivity to putative 'pheromone' components and/or allomonal components and to other reported C. capitata pheromone studies.

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A relatively simple practical method has been developed for the quantitative analysis of 2-acetyl-lpyrroline in rice samples. The rice analysis method uses a steam distillation continuous-extraction isolation procedure with an acid-phase solvent extraction. This is followed by regeneration of the basic volatiles and capillary or packed column gas chromatography analysis. Testing of the method, with a bland rice variety containing known added concentrations of 2-acetyl-l-pyrroline, showed that the method was sufficiently accurate for the purpose.

Chemical and Sensory Data Supporting the Difference between the Odors of the Enantiomeric Carvones (+)and (-)-carvone of high chemical and optical purity were synthesized from (-)-and (+)-limonene. An odor panel of 21-26 persons characterized the odor of the (+)-carvone as caraway-like and the (-)-carvone as spearmint-like. Thresholds of the natural and synthetic optical isomers were de-termined. No significant difference was found between natural and synthetic (+)-carvone or between natural and synthetic (-)-carvone. On the other hand, highly significant differences were observed between the (+)and (-)-carvones from both sources.

The basic fraction from the steam volatile oil obtained from roasted lamb fat has been analyzed by the combination of glass capillary column gas chromatography and mass spectrometry. Twelve alkylpyridines, twelve alkylpyrazines, and two alkylthiazoles were characterized. The major component of the basic fraction was 2-pentylpyridine. Other unusual compounds characterized included 5-methyl-2-pentylpyridine, 5-ethyl-2-pentylpyridine, 2-butylpyridine, 2-hexylpyridine, and 3-pentylpyridine.The volatile flavor components of meats have been reviewed by Dwivedi (1975). Lamb flavor has probably been one of the least studied.Major work in this area has, however, been recently carried out by Wong et al. (1975a,b) and Park et al. (1974Park et al. ( , 1975Park et al. ( ,1976). It has generally been considered that the main part of the flavor of lamb originates in the lamb fat. Most of the previous studies have been concentrated on the nonbasic components of lamb fat. The present study was aimed at characterizing components of the basic fraction. EXPERIMENTAL SECTIONMaterials. Lamb adipose tissue was obtained from the renal area of 4-7-month old, 80-120 lb lambs from ewes of Targhee and Finn-Targhee crosses sired by Suffolk Rams. This was kindly provided by the Animal Science Department, Lhiiversity of California, Davis. It was stored at -40 °C. Lamb fat and ground lamb were also obtained from a local market. These were refrigerated and used within a day or two of the purchase. Authentic Chemical Samples. These were obtained commercially or synthesized by well-established methods.2-Butylpyridine, 2-pentylpyridine, and 2-hexylpyridine were synthesized from 2-methylpyridine using sodium amide in liquid ammonia and the appropriate alkyl bromide (cf. Vogel, 1962). 3-Pentylpyridine was synthesized in a similar way from 3-methylpyridine. 5-Methyl-2-pentylpyridine and 5-ethyl-2-pentylpyridine were synthesized, also using a similar procedure, from 2,5-

Technical toxaphene was subjected to the following sequence of chromatographic steps to isolate those components which are of the highest acute toxicity to mice treated intraperitoneally: liquid-liquid partition column, adsorption column, liquid-liquid partition column, adsorption column, and preparative gas-liquid chromatography. Two crystalline toxicants were isolated, one a CioHioCls component 14-fold more toxic to mice than toxaphene and the other a C10H11CI7 component with a sixfold greater toxicity than toxaphene. These two compounds are fourand twofold more toxic, respectively, than toxaphene to houseflies treated topically. The C10H11CI7 component is identified as 2,2,5-endo,6-exo,8,9,10heptachlorobornane.The CioHioCls and C10H11CI7 toxicants, which make up about 6 and 3%, respectively, of technical toxaphene, appear to contribute significantly to its mammalian toxicity. These chromatographic procedures should be appropriate to isolate any individual component of toxaphene provided it is stable under the chromatographic conditions employed and a suitable monitoring technique is available.LITERATURE CITED