594 SCIENCE PROGRESS 



but particularly in the case of France, the decline is only 

 temporarily arrested (cf. figs. 2-4). Italy may claim an 

 important share in initiating the nineteenth century revival, 

 she reaches her maximum at about 1842, but is in a weak 

 position by 1 860. Austria, entering late, reaches her maximum 

 after 1850, and does not seriously go back on it, and Russia 

 also exhibits almost progressive development from 1810. 

 Scandinavia, Denmark, Holland, Switzerland, and Belgium 

 all react to the revival from about 1 820, reach a low maximum 

 shortly before or after 1840, and then undergo an almost 

 total eclipse within the next twenty years. 



As regards the subjects of study (figs. 5, 6, 7, 8, 9), mammals 

 at all times take precedence, and have received almost twice 

 as much attention as the next most popular group (arthropods). 

 The seventeenth-century revival was due chiefly to an interest 

 in the anatomy of mammals, but other groups studied then, 

 although to a much less extent, were birds, fishes, and arthro- 

 pods. Reptiles and molluscs also attracted some notice. The 

 slackening between 1700 and 1750 is observable all through, 

 except in the case of those groups, such as amphibia, echino- 

 derms, worms, and coelenterates, which were only slightly or 

 not at all studied in the earlier days. Interest in mammals, 

 however, if at a lower level, is still strongly maintained. During 

 the second half of the eighteenth century, the time of pre- 

 paration for the great revival in the following century, mam- 

 mals continue to attract the greater number of workers, but 

 the study of reptiles is still casual, and amphibia are less 

 investigated than ever. Birds, fishes, molluscs, and arthropods, 

 like the mammals, make a distinct advance, and worms and 

 coelenterates now begin to be explored effectively. Protozoa, 

 porifera, vermidea, and echinoderms have not yet succeeded 

 in attracting attention. The nineteenth-century revival 

 expresses principally an interest in mammals, arthropods, 

 fishes, and birds in the order mentioned. Worms and amphibia, 

 after the first fifteen years, i.e. from 181 5, play a considerable 

 part, and so also do reptiles, in which, however, interest has 

 been displayed from the beginning of the century. Of the 

 remaining groups, molluscs and coelenterates have been most 

 studied, but during the first thirty years of the century very 

 little work is done on protozoa, vermidea, and echinoderms. 

 Sponges are still almost completely ignored. The rapid 



