400 Scientific Intelligence — Zoology. 



species in the museums of Europe, and the number may probably 

 amount to 8000 or 10,000. 



The number of Molluscs already in collections, probably reaches 

 8000 or 10,000. There are collections of marine shells, bivalve and 

 univalve, which amount to 5000 or 6000 ; and collections of land 

 and fluviatile shells, which count as many as 2000. The total num- 

 ber of molluscs would, therefore, probably exceed 15,000 species. 



Among the articulated animals, it is difficult to estimate the num- 

 ber of species. There are collections of coleopterous insects which 

 number 20,000 to 25,000 species ; and it is quite probable, that by 

 uniting the principal collections of insects, 60,000 or 80,000 species 

 might now be counted ; for the whole department of articulata, com- 

 prising the Crustacea, the cirrhipeda, the insects, the red-blooded 

 worms, the intestinal worms, and the infusoria, as far as they belong 

 to this department, the number would already amount to 100,000; 

 and we might safely compute the probable number of species actually 

 existing at double that sum. 



Add to these about 10,000 for radiata, echini, star-fishes, me- 

 dusae, and polypi, and we have about 250,000 species of living ani- 

 mals ; and supposing the number of fossil species to equal them, we 

 have, at a very moderate computation, half a million of species. — 

 (Principles of Zoology. By Agassiz and Gould. Part i., p. 3.) 



1 1 . On Changes in the Fauna of Sweden. By Professor Nilsson. 

 {Abstracted from the Swedish. By N. Shaw, M.D.) — As a proof 

 of the oscillations or periodical changes observed in the Fauna of 

 Sweden, Professor Nilsson mentioned that the Canis Lupus, at the 

 time when Olaus Magnus published his Historia Gentium Septentri- 

 onalium, in 1535, or about 300 years ago, was very common in 

 Sweden, and, during the severe cold of the Swedish winter, exceed- 

 ingly dangerous to travellers ; but 180 years later (1735, or 24 years 

 prior to the appearance of Linnseus's Fauna Suecica), the same 

 animal had become very rare. In our days this animal has again 

 reappeared in large numbers, although by no means so numerous or 

 so dangerous as in the times of Olaus Magnus. Another animal, 

 the Vespertilio noctula, the largest of the Swedish bats, was for- 

 merly not found in Sweden, and was unknown to Linnaeus. Retzius 

 of Stockholm (who likewise published a Fauna Suecica about the year 

 1825), informs us that the Vespertilio noctula made its appearance 

 in the South of Sweden, and had become numerous in the walls of 

 the ancient cathedral of Lund. This was formerly the case ; and 

 during some late repairs on the cathedral, a number of very ancient 

 bones and skeletons of bats, the greater part of which belonged to the 

 Vespertilio noctula, were discovered in a hole in the old walls. It 

 is very clear that these bones nmst have remained in the walls about 

 700 years, and at a time when the animal was very frequent in Sweden. 

 Since that date it vanished from the counti'y, and has again in our 

 time reappeared. 



