3 1 6 Mi see llan eons. 



The Pigmy Whale (Neobalcena marginata). By Dr. Hector. 



I have the calf of this whale, 2 feet 3 inches in total length. 

 The length of the head, &c, given as the characters, are constant, as 

 in the large skull formerly figured. There is no mistake, as the 

 baleen is all in situ. I am convinced that it is not uncommon on 

 the coast of New Zealand ; but it is rarely got, as it does not grow 

 large. 



On Dolichodon Traversii. By Dr. Hector. 



Dr. Haast has a complete skeleton of this whale. I have com- 

 pared it with a pair of jaws, on board the 'Challenger,' of the true 

 D. Layardi of the Cape, and could only find a difference in the fact 

 that the teeth were not chamfered behind as in the New-Zealand 

 specimen ; the teeth are nearly locked over the muzzle, as in the 

 specimen from which the species is described in the British Museum, 

 whereas in the Chatham-Island one they are wide apart. 



Remarks on the Revivification of Rotifer vulgaris. By J. Leidt. 



Prof. Leidy remarked that during the search for rhizopods, having 

 noticed among the dirt adhering to the mosses in the crevices of 

 our pavements many individuals of the common wheel- animalcule 

 {Rotifer vulgaris), he had made some observations relating, to the 

 assertion that they might be revivified on moistening them after 

 they had been dried up. 



Two glass slides, containing beneath cover-glasses some dirt, ex- 

 hibited each about a dozen active living rotifers. The glass slides 

 were placed on a window-ledge, the thermometer standing at 80°. 

 In the course of half an hour the water on the slides was dried 

 up, and the dirt collected in ridges. The next morning, about 

 twelve hours after drying the slides, they were placed beneath the 

 microscope. Water was applied, and the materials on the slides 

 closely examined. On each slide a number of apparently dried 

 rotifers were observed ; these imbibed water and expanded, and 

 some of them in the course of half an hour revived and exhibited 

 their usual movements, but others remained motionless to the last. 



The same slides were again submitted to drying, and from one of 

 them the cover-glass was removed. They were examined the next 

 day, but several hours after moistening them only two rotifers were 

 noticed moving on each slide. 



A slide was next prepared on which there were upward of twenty 

 actively moving rotifers, and exposed to the hot sun during the 

 afternoon. On examination of the slide the following morning, 

 after moistening the material, all the rotifers continued motionless, 

 and remained so till the last moment. 



From these observations it would appear that the rotifers and 

 their associates become inactive in comparatively dry positions, and 

 may be revived by supplying them with more moisture, but when 

 the animals are actually dried they are incapable of being revivified. 

 Moisture adheres tenaciously to earth ; and rotifers may rest in the 

 earth, like the Lepidosiren, until returning waters restore them to 

 activity. — Proc, Acad. Sci. Philad. 1874, p. 88. 



