192 



CALIFORNIA ACADEMY OF SCIENCES 



The lateral line is conspicuously developed in its anterior part only, for a distance equaling the 

 length of the head. 



The dorsal spines are very slender, and increase regularly in length posteriorly, there being 

 no notch between spinous and soft dorsals. It differs in this respect from related species, there being 

 a distinct though not conspicuous notch in H. gcntilis and H. gilberli. 



The color is very light olivaceous, with black blotches and markings following the same pat- 

 tern seen in H. gilberti. Along the back is a series of six quadrate blotches, below each of which is a 

 similar smaller blotch, those anteriorly separated by a light streak corresponding in position to the 

 lateral line. Below the middle of sides is a series of dark spots arranged in seven pairs, those of the 

 anterior pairs developed as short vertical streaks. A few scattered smaller spots on head and sides of 

 body. There is a narrow V-shaped bar on occiput, a broad bar downward from eye to angle of 

 mouth, and a faint V-shaped mark on gular region. A conspicuous oval black blotch on front of 

 spinous dorsal. The fin is translucent with dusky markings not in definite pattern. A conspicuous 

 black point at the base of each anal ray. The anal is translucent, with a dusky lengthwise streak along 

 the base of the distal third of the fin. Pectorals and ventrals translucent, with some dusky markings. 



Named for Mr. C. J. Pierson, a member of the Panama Expedition, to whose 

 untiring industry much of its success was due. 



Measurements in Hundredths of Length without Caudal. 



Length in mm. to base of caudal. 



Head 



Snout 



Eye 



Gape of mouth 



Interorbital width 



Length of orbital filament 



Depth of body 



Depth of caudal peduncle 



Length of dorsal base 



Length of anal base 



Length of pectorals 



Length of ventrals 



Length of caudal 



25 

 7 



7 + 

 7 



2i 



8 

 20 



8 

 80 



53 

 22 



15 

 15 



338. Hypsoblennius striatus (Steindachner). 



Abundant in the tide-pools of the Panama reef. 



Tlie following details may be added to the original account given by Stein- 

 dachner (1877, p. 15, PI. VIII, fig. 4): 



The free tips of the rays and spines of the dorsal fin are white, the color less 

 intense than that on anal margin. The edge of the membrane between the spines 



