Sir W. Jardine on the Habits of Lepidosiren annectens. 23 



a grade as high as that which characterizes the Plagiostomous 

 Fishes ; while the elongated form of the ovaria and the con- 

 voluted disposition of the oviduct resemble more the same 

 parts in the Aocolotl, Amphiuma and Siren, 



In all its organs^ with a single exception, it is considered 

 as almost intermediate in structure ; that exception exists in 

 the organ of smell, a character ^^ which is absolute in refer- 

 ence to the distinction of Fishes from Reptiles. In every fish 

 it is a shut sac, communicating only with the external surface ; 

 in every reptile it is a canal, with both an external and in- 

 ternal opening/^ 



Further, Mr. Owen considers the Lepidosiren as typical of 

 a new family, and forming a link to connect the higher Car- 

 tilaginous Fishes with the Sauroid genera Polypterus and Le- 

 pidosteus ; at the same time, it makes the nearest approach in 

 the class, to the Perennibranchiate Reptiles. 



The specimen which we have examined was in total length 

 8|^ inches, and the body was more thickly and decidedly 

 spotted than that represented in the Linnaean Transactions. 

 The spots extend as far forward as the origin of the upper fin, 

 but are continued still further in indistinct cloudings; they take 

 the form of irregular blotches, and are largest, most distinct, 

 and in greatest numbers near the caudal extremity ; this may 

 be a variation incident to the animal, in the same way that the 

 spottings on various other fishes seldom agree. The caudal 

 fin or membrane arises gradually from the body, and the 

 scaUng is continued apparently as far as the rays reach ; above 

 this it becomes like a thin membrane, delicate and trans- 

 parent, and terminates in a minute and fine point. The whole 

 appearance in fact of this part is more like that of the mem- 

 brane which is produced at certain seasons upon some species 

 of Triton, 



The extremities, or fins if they may be so termed, present 

 some differences when compared with Professor Owen's figure 

 and description. They are each regularly barred with brown, 

 or probably, in a living state, with dark olive. In the descrip- 

 tion alluded to, ^^ the pectoral tentacles'^ are said to be " some- 

 what shorter and more slender than the ventral ones ; the 

 former are two inches, the latter two inches four lines in 

 length*." In our specimen it is just the reverse : the princi- 

 pal ray of the pectoral tentacle is attenuated to a thread-like 

 point, and is 2 inches long ; the posterior is only l|^ths inch in 

 length. They also present another discrepancy : the principal 

 pectoral tentacle is accompanied above by two short and still 

 more rudimentary members, which do not seem to have been 



« P. 3ao. 



