594 



TELEOSTEI 



to Eeinhardt ^ the allied Stego2Jliilus insidiosus, a small colour- 

 less Fish, 30 to 40 mm. long, from Brazil and Argentine, lives 

 parasitically in the gill-cavity of large Cat-Fishes {Platystoma). 

 Dr. F. Silvestri has noticed that it sucks the blood in the 

 gills of Platystoma coruscans, a Silurid growing to a length of 

 6 feet. 



Fam. 5. Loricariidae. — Distinguished from the preceding by 

 the sessile ribs and the absence of the transverse processes in the 

 praecaudal vertebrae, which have bifid neural spines. The air- 

 bladder is always much reduced, and enclosed in a right and a left 

 bony capsule formed by the skull and the anterior vertebrae. Gill- 

 openings narrow clefts. The mouth is inferior, with more or 







Fig. 359. — Upper view of heads of Chaetostomus cirrhosus, male and female. (Nat. size.) 



less developed circular lips and feeble dentition ; it is used as a 

 sucker, by which the Fish fixes itself to any hard object with such 

 strength that it cannot be pulled off without great difUculty. 

 The teeth are usually slender and bicuspid. The food consists of 

 very small prey and more or less putrefied organic substances, 

 the intestine being usually extremely elongate and much con- 

 voluted. The habits of these Fish are very little known, but the 

 fact that the males of many species have the pectoral fins much 

 stronger than the females renders it probable that they pair like 



' Vidensk. Meddel. (Copenhagen), 1858, p. 79. 



