Erythopthalmus Pipilo Eryth. **? E. Alleni P. Leucophtalmus *** Oreospiza Pipilo **? Caerulea Cyanea *** Cyanea Caerulea *** Ciris Pictus **? Calamospiza Melanocorys Melanospiza Leucoptera *** Erythrogastra Leucurus *** Iridoprocne Hirundo *** Olivacea Erythropthalmus Yes Mniotiltidae Dendroicidae **? Varia Striata **? Astiva Xantho or Auro Yes Cistothorus Telmatotytes ? Canadensis Borealis Yes [no previous columns] Erythrogastra **? _Interest in science_. By the age of 10 years D's chief interest had come to center in science and it continued to center there. His classifications of moths, birds, and the like and his observations of their life cycles are "monumental." There are volumes of these recorded observations as in Figure 9. FIG 9. ONE OF D'S RECORDS OF OBSERVATIONS. LIFE CYCLES OF BIRDS. [Here, the species of birds are listed in a column, with months of the year listed and spread out horizontally, with the first, 15th, and last days of the month underneath each month, and sometimes the 10th and 20th also. The species include: Holbcel's Grebe; Horned Grebe; Pied Billed Grebe; Loon; Loon Black-Thr.; Loon Red-Thr.; Puffin; Black Guillenot; Murre; Murre Brunnich's; Razor-billed Ank; Dovekie; Skua; Jaeger Pomarine; Jaeger, Parasitic; Jaeger, Long-tailed; Gull, Ivory; Gull, Kittawake; Gull, Glaucous; Gull, Iceland; Gull, Kumliens; Gull, Gr. Bl.-Backed; Gull, Herring; Gull, Ring-Bileed; Gull, Laughing; Gull, Bonaparte's; Gull, Little-Casual; Gull, Sabine; Tern, Gull-Billed; Tern, Caspian; Tern, Royal; Tern, Cabot's; Tern, Trudeau's; Tern, Forster's; Tern, Common; Tern, Arctic; Tern, Roseate; Tern, Least; Tern, Sooty; Tern, Black. Each bird has a line or lines to the right of its name, corresponding to the times of year.] Figures 10 and 11 illustrate his interest in physical science. They have been taken from his notebooks and state problems which occurred spontaneously to him and for which he tried experimentally to find solutions. During a series of experiments "to determine the path of a tack," it is reported that "the house was full of tacks" which had been used in attempting solutions. FIG. 10. COPY OF WORK DONE BY D "FOR FUN," MARCH 28, 1921, AGED 11 YEARS 1 MONTH. of the problem: "Determine the appearance of a finger, F, to two eyes, E#R# and E#L#, focussed on a pole R at point P#S# along lines E#R#R and E#L#R."