Two Foetuses of Lagenorhynchus acutus. Gray, 



with the incipient characters of Delpliinidæ. 



Fiu. 1. Lagenorliynchiis acutus. Gray. 110 millini. long foetus, with umbilical cord, and a considerable portion of the 

 fætal membranes, which is represented. The foetus exhibits incipient dorsal fin, distinct neck-band, and rounded 

 triangular tail-lobes. The fætal head-flexm-e is still conspicuous. The pectorals have assumed their characteristic 

 shape. The distribution of colour in the region ot the back of the neck is distinct. 

 2. Lagenorhynchus acutus, Gray, 170 millim. long fætus. The fætal head flexure has diminished considerably. 

 The Dolphin characters make their appearance. A darker colour has ditiused itself over a large portion of the 

 dorsal surface, and its distribution already indicates the specific characters. 



