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THE POPULAR SCIENCE MONTHLY. 



is matter in the right place, will take any 

 trouble not to injure books if they are ac- 

 cumulated in any numbers. . . . We suppose 

 the true reason is that, as all men respect 

 knowledge, and especially knowledge of 

 which they only dimly perceive the use, they 

 regard a library as a deposit of bottled wis- 

 dom, by which they can hardly profit, indeed, 

 but which they had rather not injure or dis- 

 perse." There are evidences that the same 

 feeling of respect for books as books has in- 

 fluence also with cultivated people. 



A Dopi (Indian) Baby. — After a child is 

 born to a Hopi Indian (says Mr. J. G. Owens, 

 in an article in the American Journal of 

 Ethnology and Archasology) the mother 

 bathes her head in a suds made of the 

 amole root, and an attendant bathes the 

 baby in a suds of the same, and rubs it, 

 except its head, in ashes, these being sup- 

 posed to kill the hair on the body. The 

 baby is then put in a cradle, and an ear of 

 corn is placed by its side to watch it. The 

 regular Hopi cradle consists of a wicker base, 

 woven of small twigs of Rhus trihbata, about 

 two and a half feet long and a foot wide. 

 Six or eight inches from one end, the head, 

 is a bow of the same material, about two 

 inches wide and nine inches high in the cen- 

 ter. This is to keep anything thrown over 

 the cradle from falling on the face of the 

 baby. Covering three quarters of the base 

 is a mat of cedar bark. Several small blank- 

 ets are laid across the cradle and the little 

 one is placed upon them, with its head gen- 

 erally lower than the rest of the body. The 

 arms are laid straight by its side, and the 

 blankets are folded over and kept in place 

 by lacing a heavy woolen cord with loops 

 of the same material on either side of the 

 cradle. Frequently the presence of a baby 

 in a house would be entirely unsuspected ; 

 but should you attempt to sit upon what ap- 

 pears to be a pile of blankets in a corner, 

 the protests of the watchful mother will at 

 once admonish you of your mistake. Until 

 the fifth day the mother must not see the 

 sun or put on her moccasins. On the morn- 

 ing of that day she bathes her own head 

 and that of the baby with amole, puts on 

 her moccasins, and is then at liberty to go 

 out of the house. She resumes charge of 

 the household affairs, and by the tenth or 



twelfth day seems to have regained her nor- 

 mal strength. Sometimes a mental record 

 of the age of the baby is kept, with the aid 

 of the fingers ; in other cases scratches are 

 made by the thumb-nail on the wall. On 

 the tenth and fifteenth days, respectively, 

 the mother again washes her head with 

 amole, and bathes and rubs the baby with 

 ashes, just as on the first day. On the 

 twentieth day the chief ceremony takes 

 place, which includes the purification of the 

 mother, the naming of the baby, and the 

 presentation of the baby to the sun. These 

 are described in detail in Mr. Owens's article. 



The Crustacean's Shell. — No group of 

 animals, says Prof. W. K. Brooks, is more 

 favorable than the Crustacea for the study of 

 the significance and origin of larval forms, 

 for these animals possess a number of pe- 

 culiarities which serve to render the problem 

 of their life history both interesting and sig- 

 nificant, and at the same time unusually 

 intelligible ; nor are these peculiar features 

 exhibited in the same degree by any other 

 great group of animals. The body of the 

 arthropod is completely covered, down to 

 the tip of each microscopic hair, by a con- 

 tinuous shell of excreted matter, and as this 

 chitinous shell is not cellular, it can not grow 

 by the interpolation of new cells, nor can 

 it, like the excreted shell of a mollusk, grow 

 by the deposition of new matter around its 

 edges, for there are no such edges, except in 

 a few exceptional cases, such as the barna- 

 cles. Once formed and hardened, the cuti- 

 cle of an arthropod admits no increase in 

 size, and as soon as it is outgrown it must be 

 discarded and replaced by a new and larger 

 one. The new shell is gradually excreted, in 

 a soft condition, under the old one, and as 

 soon as this is thrown off the new one quickly 

 becomes distended and solid. As a result, 

 from the very nature of the chitinous shell 

 and the method of renewal which its struc- 

 ture entails, the growth of an arthropod, from 

 infancy to an adult condition, takes place by 

 a series of well-marked steps or stages, each 

 one characterized by the formation of a new 

 cuticle and by a sudden increase in size. In 

 most arthropods the newly born young are 

 very different in structure from the adults, 

 and growth is accompanied by metamorpho- 

 sis. > As the changes of structure are neces- 



