462 Miscellaneous. 



TJie Winged Fruits of the Carboniferous Genus Cardiocarpus. 



The genus Cardiocarpus was probably related to the modern 

 Conifers of the Welwitschia type, as shown by the similarity of the 

 fruit and also by the close relation of the leaves, if those called 

 Cordaites belong, as both Geinitz and Newberry have independently 

 remarked, to Cardiocarpus. The Welwitschia is an embryonic form 

 of Conifer, it producing no leaves except the cotyledonous ; but, 

 while probably unlike Cordaites in its embryonic features, it shows 

 what leaves and fruit are consistent with the type of Conifers. — 

 Dana's Manual of Geology, New Edition, pp. 328, 330. 



RemarTcs on the Fishes of the Algerian Sahara. By M. P. Gervais. 



In the communications which have recently been made to the 

 Academy on the subject of the possibility of establishing a sea in the 

 Algerian Sahara, there have been urged, successively for or against 

 that project, facts derived from geology, botany, and even zoology. 

 In fact ^. Cosson, calling in the aid of this last branch of natural 

 history, has cited the Coptodon Zillii, described by me, as proving the 

 continuity of the sheet of water under this region*. 



This Coptodon, which M. Valenciennes has proposed to unite with 

 Ghjphisodon, a genus of marine fishes, although it differs therefrom 

 in several characters, and especially in the non-ctenoid character of 

 its scales, has received several other denominations. It is the Perca 

 Gayouii of Hcckel ; and Dr. Giinther has made it the type of a new 

 genus under the name of Haligenes Tristrami ; but it had been pre- 

 viously indicated under the name of Bolti from examples collected 

 in other parts of Africa, principally in the Nile ; and it is also the 

 Tilapia of Andrew Smith, who had the opportunity of observing it in 

 South Africa. It is known also in the Senegal and ^Mozambique, and 

 everywhere lives in fresh water. We cannot say, therefore, like Dr. 

 Tristram, that in Algeria it may be regarded as a last living vestige 

 of the fauna which peopled the Saharian sea during the Tertiary 

 epoch " before the elevation of the ground in Northern Africa poured 

 into the Mediterranean the waters of that vanished ocean." 



In my memoir on the fishes of Algeria f I brought forward the 

 objection which the essentially fluviatile character of the Bolti en- 

 ables us to oppose to this opinion, and indicated that this was also 

 the case with the Cyprinodon, which is likewise ejected by the 

 artesian waters of the Sahara under the same conditions ; and I 

 added that I did not think we ought any longer to accept the ex- 

 pression that has been sometimes employed with regard to this genus 

 of fishes (namely, that they are derived from a sea stretching beneath 

 the region in question), seeing that, wherever we know the Cypri- 

 nodons, they are, like the Bolti, exclusively proper to fluviatile or 

 lacustrine waters, and, like it, are strangers to the sea. This is what 

 we ascertain, whether we observe these fishes in Algeria or captui-e 

 them in Portugal, Spain, Syria, Egypt, and even in America. More- 

 over the fossil Cyprinodonts which Agassiz names Lehias are like- 



* See ' Comptes Rendus,' tome Ixxix. p. n34. 

 t Zool. et Pal. gen. p. 200. 



