522 The Blennies: Blenniidae 



occurs in Formosa. In this species, alone of the sand-lances, 

 the ventral fins are retained. These are jugular in position, 

 as in the Zoarcida, and the rays are I, 3. The discovery of 

 this species makes it necessary to separate the Ammodytidce 

 and Bieekeriidce widely from the Percesoces, and especially from 

 the extinct families of Crossognathida and Cobitopsida with which 

 its structure in other regards has led Woodward, Boulenger, and 

 the present writer to associate it. 



Although an alleged sand-lance, Rhynchias septipinnis, with 

 ventral fins abdominal, was described a century ago by Pallas, 

 no one has since seen it, and it may not exist, or, if it exists, it 

 may belong among the Percesoces. The relation of Ammodytes 

 to Embolichthys is too close to doubt their close relationship. 

 According to Dr. Gill the Ammodytidcs belong near the Heme- 

 roccetidce. 



The Pearlfishes: Fierasferidae. In the little group of pearl- 

 fishes, called Fierasferidcs or Carapida, the body is eel-shaped 



FIG. 476. Pearlfish, Fierasfer dubius Putnam, embedded in a layer of mother-of- 

 pearl. La Paz, Lower California. (Photograph by Capt. M. Castro.) 



with a rather large head, and the vent is at the throat. Numer- 

 ous species of Fierasfer (Campus) are found in the warm seas. 

 These little fishes enter the cavities of sea-cucumbers (Holo- 

 thurians) and other animals which offer shelter, being frequently 

 taken from the pearl-oyster. In the Museum of Comparative 



