INDUSTRIAL PROGRESS DURING THE YEAR 1876. cxlvii 



abiogenesis. In some, at least, of the septic organisms spores are 

 demonstrably produced, and these spores can resist a temperature 

 nearly double that of adults on the average ; that which some can 

 resist is 88 Fahr. above the boiling-point of water." This, adds 

 the Quarterly Journal of Microscopical Science^ is in harmony with 

 the experiments of Roberts, and the later ones of Huizinga. 



In a little book entitled '* Half- Hours with Insects," the writer 

 .cites a number of unpublished facts regarding mimicry in insects, 

 and inclines to the belief that the resemblance in pattern and color 

 between insects belonging to different groups is probably due to 

 causes more fundamental than natural and sexual selection, and 

 reaching possibly farther back in geological time than the present 

 period. The majority of mimickers of other insects belong to 

 groups lower in the organic scale than the insects they mimic, and 

 may have been preserved by virtue of their resemblance to butter- 

 flies originating at a later date. 



In his address at the last meeting of the British A.ssociation for 

 the Advancement of Science, Professor Alfred Newton adverts to 

 the subject of the extinction of animals by natural and artificial or 

 human causes. " It is notorious," he says, " that various members 

 of the orders Sirenia^Cetacea^ and Pinnipedia have recently dwindled 

 in numbers, or altogether vanished from the earth. The manatee 

 and dugong have been recklessly killed off from hundreds of local- 

 ities where but a century or so since they abounded, and with them 

 the stores of valuable oil that they furnished have been lost. That 

 very remarkable Sirenian, the huge Rhytina gigas, has become utter- 

 ly extinct. The greed of whalers is believed to have had the same 

 effect on a cetacean (the Balcena Mscayensis) which was once the 

 cause of a flourishing industry on the coasts of France and Spain. 

 The same greed has almost exterminated the right-whale of the 

 northern seas, and is fast accomplishing the same end in the case of 

 seals all over the world." He also speaks of the alarming decrease 

 of fish and edible mollusks. 



Perhaps the most remarkable biological work of the year is Pro- 

 fessor August Weismann's treatise on the " Final Causes of Trans- 

 mutation," forming the second part of his studies on the " Theory 

 of Descent." The first part of the work, entitled " Seasonal Dimor- 

 phism," was noticed on p. cxciv. of the Annual Record for 1875. The 

 present work is divided into three divisions, of which the first pre- 

 sents an array of facts on the origin of the markings of caterpillars. 

 The author describes the nature and morphology of the markings 

 of larva3 of the family Sphingidce^ their biological value, and phyletic 

 development, concluding that the oldest sphingid cateqDillars were 

 without markings, that the oldest style of markings were longitudi- 

 nal lines, the later ones oblique streaks, and the last to be developed 

 were the spots. This part of the subject is illustrated by five colored 



