nr\ 



06 ANNUAL OF SCIENTIFIC DISCOVERY. 



month of Ajn-il, noar Paris, several spccimcMis, of both sexos, in 

 which the gcneiativo apparatus was perJcctly dovoloped, while 

 the JK'-ad, branohia?, limbs, tail, and all the rest of the boily showed 

 the dovelopmcMit oidy of the tatlpole state. 



Strafijlcdddn of Gikuw. — Guano has been considered as a sim- 

 ple accumulation of tiie excrements of birds; but M. Ilabel, as 

 stated in an abstract of a seven years\journey in tropical America, 

 published in the " Comptes Rendus," for July 2G, l.SGO, found this 

 substance at the Chincha Islands ve2:ularly stratitied, ]ik(! all the 

 sedimentary rocks, with layers of diilerent colors, inclination, and 

 extent. Some layers, for instance, in a part of one of the islands 

 he found with an inclination of 5 degrees, and in another part of 

 the same island of lo degrees. In one part of the southern island 

 he saw layers running from N. to S., with an inelinaiion of 4 de- 

 grees, covered by others from S.W. to N.E., with an inclination 

 of 20 degrees. It is very evident that there have been two epochs 

 in the formation of guano; the lower, older, and more extensive 

 mass is stratified, while the upper, more recent, and thinner, is 

 without stratification. Below the guano, there are layers of sand 

 more or less mingled with guano; and in some places it is easy 

 to see that the lower hu'ers contain much less guano than the up- 

 per. He found l)ones of birds, not only in the ditferent layers of 

 guano, but in the underlying sand and sandstone. Tiiis would 

 seem to indicate that geological causes were concerned in the 

 deposition or subsequent condition of guano. 



Fishes with External Gills. — i\I. Sleindaehner, of Vienna, has 

 described a new species of roli/pterusi'vom Senegal, F. Lapiadei, 

 which, as well as F. Sengeahis, has external branchia? in tlu; young. 

 In the new species they existed in individuals about 19 inches 

 long, as a long ilattencd band, fringed on the edge, on each side, 

 behind the opcirculum, and extending beyond tiie posterior bor- 

 der of the pectoral lin, very like the external branchiie of the 

 batrachian axolotl, but single instead of triple. In the other spe- 

 cies, this transition organ disappears earlier, when the fish is about 

 4 inches long. It would be interesting to know if the species of 

 the Nile has a similar apparatus wdien young. The sharks, rays, 

 and African Fvotoj)terusangiiilliformis are not, therefore, the only 

 fishes provided with external branchia?. Prof. Ilyrtl has shown 

 that these organs in the above new ganoid fish ])erform the func- 

 tion of respiration. — Comptes Rendus, Oct. 18, IbJGD. 



Vitality of tlie Sponge. — According to the experiments of ^I. 

 Vaillant on the Tcihya lynau-iiun (Lam.), a sponge common on 

 the coast of Brittany, the cortical substance, when isolated, will 

 reproduce the medullary substance, and vice ver.sa. Tlie vitality 

 of the cortical substance is, however, greater than that of the 

 nKjdullary ; it can reproduce the prolongations by which the sponge 

 is attached, and serves to protect the softer interior. Ditferent 

 individuals of this species may be united by grafting, after a suf- 

 ficient lime; but hitherto this union has not been eflected with 

 individuals of another genus. — Comptes Jicndus, January, 1809. 



jfksAi- of the Mammoth. — According to Mr. Woodward, all the 



