58 U.S. NATIONAL MUSEUM BULLETIN 2 84 



The number of segmented rays varies from 10 in Stanulus to 119 in 

 Xiphasia, with most genera having fewer than 25. With the exceptions 

 of Stanulus and Pereulixia there are always more rays than spines. 

 Usually the rayed portion of the dorsal fin is higher than the spinous 

 portion, but in Blennechis Jilamentosus, Blennius ocellaris, Blennius 

 normanif and males of Blennius nicholsi and Omobranchus lini, the 

 lengths of the anterior dorsal spines greatly exceed those of the rays, 

 and in some species of Ecsenius the posterior dorsal spines may exceed 

 the lengths of the rays. There are no gaps in the dorsal fin that would 

 indicate the dropping out of a spine (or its associated proximal pte- 

 rygiophore) as is common in the Clinidae. The terminal spine and the 

 first ray are always articulated with the same proximal pterygiophore. 

 This feature is of value in making dorsal element counts from radio- 

 graphs of damaged specimens. 



The rays, except for the posteriormost, each articulate with small, 

 bilaterally paired distal pterygiophores, which in turn articulate with 

 an unpaired proximal pterygiophore that may embody the medial 

 pterygiophore of more primitive teleosts. The posteriormost ray may 

 lack the paired distal pterygiophore. The presence or absence of the 

 terminal distal pterygiophore is fairly constant within a species or cer- 

 tain groups of species, but much more data are required to determine 

 the significance, if any, of this condition. In general, the Nemophidinae, 

 Omobranchini, and Blenniini tend to have the terminal distal pte- 

 rygiophore; the condition in the Salariini is variable. 



Anal fin. — The anal fin invariably has two spines with the unusual 

 intraspecific variant having one or three. The first spine in females 

 usually is reduced and frequently is noticeable only in osteological 

 preparations or on radiographs. The segmented anal rays vary in num- 

 ber from 11 in Stanulus to 119 in Xiphasia, with most genera having 

 fewer than 25. The number of segmented anal rays usually exceeds 

 the number of segmented dorsal rays by one or two, but may equal 

 them or be as many as 11 fewer in number (Meiacanthus) . The anal 

 spines are attached only to proximal pterygiophores. The second anal 

 spine and the first segmented ray are attached to the same pterygio- 

 phore. The rays, except for the posteriormost, articulate with paired 

 distal pterygiophores, which in turn articulate with proximal pte- 

 rygiophores that may embody the medial pterygiophore of more 

 primitive teleosts. The presence or absence of the terminal distalptery- 

 giophores is correUated closely with its presence or absence in the dorsal 

 fin (q.v.). 



In some genera and some species of the Salariini {Entomacrodus, 

 Stanulus, Istiblennius, Ophioblennius, Scartichthys, Exallias, Per- 

 eulixia, Halmahlennius) , the terminal proximal anal pterygiophore 

 typically supports two rays, the posterior of the two much reduced in 



