Classijication of the Ordtr Pediculati. 



279 



case tliat the resemblances in osteological characters, 

 especially in the structure of the pectoral arch, are not 

 due to real affinity. In many ways the Batraciioids are 

 more generalized than tiie typical Pediculates, but in some 

 respects, notably the reduction in number of the pelvic fin- 

 rays and the ankylosis of parietal and epiotic, they are more 

 specialized. Tiie Pediculates might certainly be regarded as 

 liighly specialized Percoids, were it not that in the Perco- 

 morplii all the principal hypurals are attached to the last 

 vertebra, whereas in the Batraciioids the upper hypural plate 

 is ankylcsed to the last half-centrum, and that supporting 

 the lower halt of the fin is united to the preceding centrum, 

 much as in the Salinopercai ; this seems to be a primitive 

 character. 



Suborder 1. Batrachoidea. 

 Spinous dorsal post-cephalic, of 2 to 4 pungent spines, 

 with fixed basalia : each pelvic fin of a spine and 2 or ^ 



l-i^^ •3. 



Skull of Batrachoides didadylus. from above aud from below. 

 r, vomer ; leth, lateral ethmoid : /, frontal ; p, parietal ; soc, supra- 

 occipital ; ex, exoccipital ; boc, ba-^ioccipital ; spo, sphenotic ; 

 pto, pterotic ; pro, pro-otic ; psp, parasplienoid ; asp, alisphenoid ; 

 ptte, post-temporal ; na, neural arch, and c, centrum of first 

 vertebra. 



soft rays. Gill-opening in front of base of pectoral ; gills 3, 

 none on the fourth branchial arch. Epiotics absent, or anky- 



19* 



