1886.] NATURAL SCtENCES OP PHILADELPHIA. 237 



at all from descriptions of the European pungitius, but I have 

 had no specimens of the latter for direct comparison. I cannot, 

 therefore, regard occidentalis as a separate species or variety. 

 The dekaiji of Agassiz is based on the occidentalis of Dekaj' ; 

 I have therefore placed it also in the synonymy of pungitius. 



The mainensis of Storer is said to differ from pungitius only 

 in having a " bony serrated plate on the side." This probably 

 refers to the plate behind the pectorals. 



The concinnus of Richardson is said to differ in having seven 

 dorsal spines, but as the number seems to vary from 7 to 11, this 

 cannot be considered as a specific character. I have examined 

 specimens from Calumet, R. Illinois (presumably representing 

 the form called nehulosus). I can find no difference whatever 

 between these and Massachusetts examples of pungitius. 



The var. hrachypoda seems to differ from pungitius only in the 

 shorter ventral spines. It is known to me only from the descrip- 

 tion of Dr. Bean (above cited). 



2. EUCALIA. 



Eucalia 3ovA.2ia, Man. Vert,, ed. i, 248, 1876 (inconstans) . 



This genus is closely allied to Pygosteus, agreeing with it in 

 the structure of the gill membranes, but differing in having the 

 dorsal spines few and non-divergent, and in having the innomi- 

 nate bones more fully united. The species are the most feebly 

 armed of the Sticklebacks. 



Analysis of Species of Eucalia. 



a. Body moderately robust, the caudal peduncle not very slender; 

 depth 4 in length to base of caudal. Head pointed ; 

 mouth small, very oblique ; maxillary reaching to anterior 

 margin of eye ; teeth small, stout, in a single series ; 

 eye large, much longer than snout. Caudal peduncle 

 moderately compressed, 7^ times in length to base of 

 caudal. No bony dermal plates ; skin naked ; no post- 

 opercular (suprascapular) plate ; post-pectoral plate covered 

 by skin ; skin of head not ossified. Lateral line beginning 

 at upper angle of preopercle and curved to below fourth 

 dorsal spine, from where it goes straight to middle of tail ; 

 a second row of tubes is seen for a small distance along its 

 origin. A patch of mucous pores at beginning of lateral 

 line ; a row along the edge of the preopercle and a c-shaped 



