INDUSTRIAL PROGRESS DURING THE YEAR 1875. clxxxix 



surrounds one half of the yolk. In the next stage observed 

 the antennae and three pairs of jaws are developed (only two 

 in the thousand-legs). In a succeeding stage the primitive 

 band is much longer than before, and the head and tail ap- 

 proach nearer to each other, while there are now from forty- 

 four to forty-six body-segments, most of them bearing rudi- 

 mentary appendages, though there are none as yet on the 

 end of the body. In a succeeding stage the head is much 

 larger, the body longer and curved over the yolk, while the 

 eo-o--shell breaker is situated on the second maxillre. In a 

 following stage the body is still more elongated and the 

 joints of the antenna? appear. The embryo now slips out 

 of the split shell, the body being very long and cylindrical, 

 not yet flattened as in the adult animal. 



The young Geophilus, and probably nearly all the centi- 

 pedes, undergoes no metamorphosis, being born with nearly 

 the full number of feet, while the young thousand-legs or 

 millepede has but three pairs when hatched. We now have, 

 thanks to Metschnikoff's other papers on the development 

 of the Chelifer and Scorpion, and to the researches of other 

 observers, quite full information regarding the life-histories 

 of the tracheate Arthropods, or insects. 



Unusual activity has been shown by students of the spi- 

 ders both in Europe and this country. The writings of 

 Hentz have been collected and republished by the Boston 

 Society of Natural History, containing the text and plates 

 of his papers in the memoirs of that society, with the addi- 

 tion of several excellent plates drawn by Mr. J. H. Emerton, 

 with additional notes by him. A number of new species of 

 spiders from Southern Europe and North America, belonging 

 to the genus Erigone, are described by the Rev. O. P. Cam- 

 bridge. Dr. Thorell has described a number of new forms 

 from New Caledonia, Madagascar, and Reunion Islands. It 

 appears that the Nephila edalis Vinson, of New Caledonia, 

 a large spicier allied to our Nephila phimipes, whose hab- 

 its have been studied by Professor Wilder, is used by the 

 natives as an article of food, while in Madagascar JVephila 

 Madagascar iensis Vinson, is also eaten, "en l'accommodant 

 avec de l'huile ou de la graisse " (see Vinson, "Voyage a Mad- 

 agascar," p. 126). He also gives some notes on venomous spi- 

 ders. The so-called venomous spider of Madagascar, called 



