cold; all these together and a soil 

 on which a strange stunted under- 

 brush grows, form its characteris- 

 tic landscape. 



There are large beds of infusor- 

 ial earth 300 to 400 feet thick and 

 extremely light. The surface is 

 bleached intensely white by the 

 sun burning out the little asphalt 

 oil on top. Underneath is a brown, 

 impalpable dust like volcanic ashes 

 — a mighty ash heap and yet com- 

 posed of shells of the infusoria, vis- 

 ible only under a powerful micro- 

 scope. 



From the presence of this dust 

 it may be taken that asphalt is in- 

 fusorial also, being formed out of 

 animal matter, of infusoria, while 

 the mineral matter, or white shell 

 dust, remains above it. 



There are beds of brown sand, 

 almost a sandstone, parallel to the 

 direction of the asphalt deposits, 

 and seemingly underlying them in 

 the strata. This brown sand co- 

 heres through the agency of as- 

 phaltum material in it, and has 

 stood like a dike against the ero- 

 sion of geological periods. 



One more interesting feature of 

 the district is the mineral tar, as it 

 is commonly called, or liquid as- 

 phaltum. It exudes in many places 

 and trickles down hill until a hol- 

 low is reached and black pools are 

 formed. In those pools lizards, 

 beetles, rabbits, birds, and even a 

 deer and a bear have been found, 

 all embalmed by the liquid that 

 kills them.- — Baker sfield Califor- 

 nia n. 



Reproduction in Animals. 



In animals there are two kinds 

 of reproduction — sexual reproduc- 

 tion and asexual reproduction. 

 For sexual reproduction two kinds 

 of cells are necessary, the egg, or 

 germ-cell and the sperm-cell, com- 

 ing generally from distinct individ- 

 uals. From the union of these 

 two cells the embryo is developed. 

 The essential parts of the gem- 

 cell or egg, are three, viz., the 

 germinal vesicle, which prehistri- 

 mary part, being a particle of pro- 

 toplasm, the yolk, which serves as 

 food for this, and the vitelline 

 membrane, in which the germinal 

 vesicle and the yolk are enclosed. 

 When a large amount of yolk is 

 present, it may be divided into 

 formative yolk and food yolk. 

 Food yolk is distinguishable from 

 formative yolk by its more oily 

 nature. The structure is more 

 complicated in the egg of the hen. 

 Externally is a hard, porous shell, 



NATUKAL SCIENCE NEWS. 



consisting of a deposit of lime in a 

 net-work of animal matter. Lin- 

 ing this is the mcmbrana putaminis, 

 a delicate, double membrane, which 

 separates at the larger end to en- 

 close air for the chick's use. Next 

 in order is the albumen, in layers 

 arranged spirally, and within this 

 is the vitelline membrane contain- 

 ing the yolk. On the outside of 

 the yolk is a white spot of cellular 

 structure, the cicatricula, or em- 

 bryo-spot. It is, however, no 

 longer in its initial stage, develop- 

 ment having already advanced be- 

 fore the laying of the egg. 



The shell and albumen are want- 

 ing in most eggs, or when albumen 

 is present it is usually covered only 

 by a tough membrane. The en- 

 velope of the eggs of Crocodilia is 

 like that of birds, while in Carchar- 

 ias vulgaris it is of a horny texture. 

 The egg of the Sponge resembles 

 an amoeboid cell. It is the quan- 

 tity of yolk which mainly deter- 

 mines the size of an egg. The 

 yolk is minute and formative in 

 the eggs of an Astcroidca, Vermes, 

 Insecta, Mollusca (excepting the 

 Cuttle-fishes), numerous Amphibia, 

 and Mammalia, while it is large 

 and colored and consists of the 

 formative and nutritive parts in the 

 eggs of Lobsters and Crabs, Cepha- 

 lopoda, Araneina, Pisces, Rcpiilia 

 and Aves. 



The eggs of Crocodilia and Aves 

 are elliptical or oval in shape; of 

 Vespa and Che Ionia, spherical; of 

 Dipt era and of the Apis and Bom- 

 bus, cylindrical; and of the Car- 

 charias vulgaris they are shaped 

 somewhat in resemblance to a 

 hand-barrow, having tendrils on 

 the corners. In some of the low- 

 est forms the eggs are covered with 

 prickles or hairs. 



Concerning the number of eggs 

 of different animals there is a great 

 variance, proportional to the risks 

 during development. The Cjueen- 

 bee lays about a million eggs dur- 

 ing her life, and the spawn of an 

 Oyster contains 6,000,000. 



As far as the care of the eggs 

 after deposition is concerned, it is 

 a general rule that those animals 

 which receive the longest and best 

 care while in the embryo state, 

 ultimately attain the highest step 

 of development. 



The Protozoa reproduce by con- 

 jugation. Two individuals unite 

 into one mass, and surround them- 

 selves with a case. Within this 

 they divide into several parts, each 

 of which becomes a new individual. 

 The Sperm-cell differs from the 

 egg in the following respects: it is 

 generally motile, very small, and 



from one reproductive cell a large 

 number of them are usually pro- 

 duced, which is not the case with 

 the egg, that being the entire pri- 

 mary cell. Development occurs 

 only when there is a union of the < 

 sperm-cell with the germinal ves- i 

 icle. 



Asexual Reproduction is of two 

 kinds — self-division and budding. 

 Self-division is the separation of 

 the body into distinct parts of ; 

 which each is then a new animal. 

 This division may be either longi- 

 tudinal or transverse. Only those 

 animals whose organs and tissues 

 are simple in structure and easily 

 bear division have this form of 

 asexual reproduction, as, for in- 

 stance, Protozoa, Polyps and 

 Vermes. 



Budding is somewhat akin to 

 self-division. In self-division the 

 off-spring receives a part of the 

 parent's organs, while in budding 

 one or more cells of the original 

 animal develop and multiply and 

 grow into an animal resembling 

 the parent. Sometimes the buds 

 remain attached to the parent 

 stock, forming a colony as in Bry- 

 ozoa and Corals, and the process 

 is then called continuous budding. 

 In Hydra, Aphis and Daphnia this 

 separation takes place when the 

 bud is developed, while among 

 some animals these buds are inter- 

 nal, and are separated when no de- 

 velopment has taken place, and 

 then resemble an egg in appear- 

 ance. Nevertheless they develop 

 without fertilization, differing in 

 this respect from a true egg. 



O. A. Dahms, 

 Davenport, Iowa. 



Object Teaching in Town and 

 Country. 



Decidedly things are moving. 

 Constantly, some say too constant- 

 ly, we urge the necessity of a re- 

 turn to nature in our methods 

 of elementary education. The 

 art of printing has done much 

 for man, but the printed page too 

 often inserts itself between our 

 eyes and the realities of the world. 

 Our cry, therefore, has always 

 been — less book teaching, less giv- 

 ing of information, let children 

 learn for themselves by the old 

 way of the five senses, let science 

 be learned by the individual as it 

 is learned by the race, through ob- 

 servation and experiment. But, as 

 we said, things are moving, and 

 soon there will be little left for us 

 to urge. 



In our April number we men- 

 tioned the addition to the Educa- 



