386 Miscellaneous. 



Jeucle's Museum in Holland, and therefore probably from the Dutch 

 colonial possessions, are all of a much smaller size, not half the size 

 of those from South Africa (see figure of Fells pardus sumatranus, 

 Blainv. Osteogr. Fells, t. viii.), which seems to represent a small 

 specimen of this latter variety. Blainville represents a smaller 

 skull, still under the name of Fells pardus barbarus, from Barbary, 

 North Africa (t. viii.). 



The leopards have a narrow opening at the back of the palate, 

 and a tooth-like prominence on the front edge. This character 

 seems common to all the leopards, but is more marked in some 

 than in others. 



They seem to vary in the width of the opening to the posterior 

 nostrils. In some it is very narrow, and in others broader ; this is, 

 perhaps, a sexual character. 



The puma, the skull of which very much resembles that of the 

 leopards, differs from the leopard in having the front edge of the 

 hinder opening of the nostrils simply rounded. 



On the Ethology of Sacculina carcini. By M. A. Giard. 



Cancer mamas, like all those animals which are very common and 

 capable of suiting themselves to very varied conditions of existence, 

 is subject to the attacks of a multitude of parasites and commensals 

 belonging to the most various groups of the animal kingdom. Among 

 these parasites one of the most interesting is unquestionably Saccu- 

 lina carcini, the curious metamorphoses of which we have recently 

 studied. 



The Sacculina is very common at many points of the coasts of 

 Brittany ; it becomes rare on the shores of the Boulonnais and of 

 Flanders, from Cape Gris-JNez to Dunkirk. On the other hand, it 

 is excessively abundant at Ostend, where it was long ago noticed 

 by M. P. van Beneden, and where I have myself found it by hundreds 

 this summer. 



As the Sacculina inevitably causes the sterility of the crab which 

 bears it, at first mechanically and afterwards histologically, Cancer 

 mamas, notwithstanding its prodigious fecundity, would soon become 

 rare upon the shores on which an equally fertile parasite swarms, 

 if many causes did not cooperate to limit the excessive multiplication 

 of this curious llhizocephalon. 



At Ostend we often find under the tails of crabs which bear Sac- 

 culince small tufts of Bryozoa and strings of young mussels, which 

 appear to hamper considerably the development of the parasite under 

 consideration. At Wimereux, where the edible mussel is also very 

 common, the same fact is frequently observed; but as the mussel 

 can rupture its byssus and quit its place at pleasure, when it finds 

 itself inconveniently confined, it does not constitute a great danger 

 for its neighbour the Sacculina. 



This, however, is not the case with Molgula socialis, the active 

 larvae of which often take up their abode under the tail of C. mcenas 

 when this is raised by the Sacculina. These Ascidia, as they are 

 developed, gradually compress the body of the Sacculina and finally 

 cause it to perish, after hindering its multiplication for some time. 



