Science . and d from 46th Ann. Rep. Reg. , etc., England and Wales, p. xxxi. Age Scale.—1,000 individuals, in age-groups of5 and 10 years «lrt2 0 - 5 5 - 10 10 - 15 15 - 20 20 - 25 25 - 35 35 - 45 45 - 55 55 - 65 65 - 75 75 — OD r2 1000 1 e a) da 136 138 120 116 107 106 97 97 89 87 147 148 113 116 86 87 59 59 33 33 13 13 It will be seen that in the above examplethe values calculated for the age-scale andespecially for h and d, show a good agreementwith the observed values. The above development admits of furtherextension. But this, as well as furthernumerical tests, must be reserved
Science . and d from 46th Ann. Rep. Reg. , etc., England and Wales, p. xxxi. Age Scale.—1,000 individuals, in age-groups of5 and 10 years «lrt2 0 - 5 5 - 10 10 - 15 15 - 20 20 - 25 25 - 35 35 - 45 45 - 55 55 - 65 65 - 75 75 — OD r2 1000 1 e a) da 136 138 120 116 107 106 97 97 89 87 147 148 113 116 86 87 59 59 33 33 13 13 It will be seen that in the above examplethe values calculated for the age-scale andespecially for h and d, show a good agreementwith the observed values. The above development admits of furtherextension. But this, as well as furthernumerical tests, must be reserved for a futureoccasion. In view of the recent note of thework by Major Woodruff, it appeared de-sirable to the writer to publish this pre-liminary note. Alfred J. Lotka A NEW GENUS AND SPECIES OP FOSSIL SHARKRELATED fo EDESTUS LETOY The specimen which serves as the type ofthe new genus and species, Lissoprion ferrieri,was secured in what are regarded as Permo-Carboniferous deposits near Montpelier, Bear. Lake County, Idaho. It was collected by F. Eerrier, of the town mentioned. Thespecific name is given in his honor. The The calculation is based on the observed valueof r=.0141, as indicated by the brackets. JULY 1907] SCIENCE 23 specimen was transmitted to me by Mr. FredBoughton Weeks, of the U. S. GeologicalSurvey. Three segments are represented in the speci-men, as shown in the drawing. As in Edes-Liis, there are enameled crowns of teeth sup-ported on a shaft of vasodentine. Two ofthe ci-owns are practically complete, the thirdlacks a considerable portion. Much of theshaft is splintered off, so that its form anddimensions can not be determined. Evidently our fossil does not belong to thegenus Edestus, for not only are the bases ofthe teeth fused so that no traces of the con-stituents appear in the shaft, but the crownsthemselves are fused to more than one halftheir height. The crowns differ from those ofall the known species of Edestus in being de-void of all serrati
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