470 



SCIENCE. 



[Vol. IV., No. 94. 



their movements were rapid, and the number engaged 

 at one time must have been fifty, while it is probable 

 that a hundred were at work, for they were constantly 

 coming from various directions to take or resume their 

 places on the up-stream side of the dam. 



The river-bed at this point was made up of water- 

 worn stones, chips of granite, and fragments of bricks, 

 over which there was a steady flow of water, the depth 

 being four or five feet, but varying with the level of the 

 tide. 



The mode of raising the material was the same in 

 all cases : the eel attached his mouth to a stone, and 

 then, with many wrigglings and contortions (the head 

 always pointing up-stream), lifted it from the bottom ; 

 he then backed down stream, floating with the cur- 

 rent, until the stone was over the centre of the heap, 

 when it was dropped, lodging sometimes on one side, 

 and sometimes on the other. He then usually re- 

 turned for more material to the deep and compara- 

 tively still pool formed above the dam by the previous 

 excavations, but in some instances was unable to stem 

 the more rapid current at the top of the dam, and 

 was carried below it. When this happened, he swam 

 around the outer end of the dam, and returned to the 

 pool to resume the work. 



I noticed in many instances that the heavier stones 

 were lifted by two eels, working alongside of each 

 other, and carried to their proper places in the struc- 

 ture. Half-bricks, weighing two pounds, were thus 

 transported by one individual, and many of the stones 

 were of much greater weight. 



Later in the season many of the eels were lying 

 quietly upon the up-stream side of the dam, and about 

 the middle of July all had disappeared. 



The temperature of the water, when the river-cur- 

 rent was not met by the tide, was in June about 64° 

 F., and in July 71°. 



Stones of various sizes, lying at the base of the 

 shore-wall, were removed; and it was evident that the 

 stability of this wall would have been impaired if it 

 had been built upon a rubble or gravel foundation 

 instead of upon a solid ledge. 



John M. Batchelder. 



Cambridge. 



A viviparous pumpkin. 



To-day, on cutting open a common pumpkin fresh 

 from the field and perfectly sound, it was discovered 

 that very many of the seeds had already germinated. 

 The caulicles were from one to three inches in length, 

 while some of the rootlets were over seven inches. 

 The cotyledons, wherever free from the seed-cover- 

 ing, were green in color, and spread so as to expose 

 the growing plumule. In one case the second leaves 

 were partly unfolded. E. T. Nelson. 



Delaware, O., Nov. 1. 



American pearls. 



In answer to George F. Kunz in No. 89, let me say 

 that many pearls, ranging from five to twenty-five or 

 more dollars in value, have been found in the fresh- 

 water mussel in the Little Miami Kiver, a few miles 

 from here. The prevailing color is pink, in various 

 shades. In size they vary, the larger ones being about 

 as large as a pea, or larger. The pearls have been 

 found at various times, from a dozen years ago, up to 

 last April. They are commonly found in the Unio, 

 — U. undulatus, or U. occidens. R. N. Eoark. 



Nat. science dept., Normal university, 

 Lebanon, O. 



FERDINAND VON HOCHSTETTER. 



Ferdinand von Hochstetter was born at 

 Esslingen (Wurtemberg) , April 30, 1829, and 

 died, after a painful illness of five years, at. 

 Vienna, on the 17th of last July. His father, 

 a clergyman, was a well-known botanist, and a 

 professor of natural histoiy. While a pupil of 

 the celebrated geologist and paleontologist, 

 Prof. F. A. Quensted of Tubingen, Hochstteter 

 was a classmate of the late A. Oppel, and is 

 one of the most prominent of the geologists of 

 the school to which science is indebted for 

 such celebrated geologists and paleontologists 

 as Oscar Fraas of Stuttgart ; C. Rominger 

 of Ann Arbor, Mich. ; A. Oppel, and Traut- 

 scholcl, of Moscow. When an assistant in the 

 Austrian geological survey, he was appointed 

 naturalist of the ' No vara expedition round 

 the world,' 1857-59. After visiting Gibraltar, 

 Rio de Janeiro, the Cape of Good Hope, St. 

 Paul Island, the Mcobar Islands, and Java, 

 Hochstetter left the No vara, shortly after its- 

 arrival at New Zealand, and passed almost 

 the whole of 1859 in preparing a careful geo- 

 logical reconnoissance of the northern and 

 southern islands of New Zealand. Scarcely 

 had the Novara anchored at Auckland, before 

 Julius von Haast, an Austrian nobleman of 

 great ability, well known afterward as the di- 

 rector of the Canterbury museum of Christ- 

 church, came on board. Haast had come out 

 a short time before as a settler. Hochstetter 

 at once secured him as his assistant ; and after 

 seven months in the northern island, and two 

 months in the province of Nelson in the south- 

 ern island, with the aid of the New-Zealand 

 government and of the leading citizens of the 

 colony, he succeeded in determining most sat- 

 isfactorily the geology of this distant country, 

 describing not only the beautiful volcanic for- 

 mation, but also the secondary, the tertiary, 

 and the quaternary formations, and adding 

 much to our knowledge of geographical geol- 

 ogy. The results of Hochstetter' s researches, 

 were first given as lectures before the Auck- 

 land mechanics' institute, June, 1859, and 

 at Nelson in October of the same year. The 



