154 LOPHIOIDS. 



cipally inserted into the inner straight margin of the base of the 

 tooth, from which their glistening fasciculi radiate to be implanted into 

 the jaw. The rest of the base of the tooth is connected at its circum- 

 ference with more lax and yielding fibrous bands, and with the 

 mucous membrane of the mouth, which covers the alveolar tract in the 

 interspaces of the teeth. To any attempt to bend these teeth out- 

 wards resistance is offered by the internal ligaments above described, 

 and by the pressure of the anterior angle of the base of the tooth 

 against the alveolar process or raised tubercle on which it rests ; 

 but the tooth readily yields to a force acting in the opposite direction, 

 and the largest and most prominent teeth can be bent inwards and back- 

 wards so as to point to the gullet when the hand is pressed over them 

 in the direction a body would take when drawn into the mouth to be 

 swallowed : the moment, however, this force ceases to act, the teeth 

 recoil to their erect position, as if operated on by a spring. If every 

 thing attached to the base of the tooth, excepting the internal pyra- 

 midal band of ligamentous fibres, be removed, the tooth, after being 

 bent down, returns with the same force to the erect position ; it is, 

 therefore, to this band that its resilience is due. 



The teeth of the Lophius exhibit, as stated in the first chapter, 

 the higher type of dental structure : such as characterizes the teeth 

 of sauroid fishes and of most reptiles and mammals. The fully- 

 formed teeth are constituted by a single system of calcigerous tubes, 

 radiating from a single sub-central pulp-cavity : this is widely open 

 at the base of the tooth, but soon diminishes by the convergence of 

 its sides, which arch inwards and meet at the basal third of the 

 tooth, whence the pulp-cavity is continued as a mere line to near its 

 apex. The course of the calcigerous tubes is unusually uniform, 

 throughout the entire length of the tooth. On leaving the pulp- 

 cavity they ascend obliquely and then incline in a graceful curve to 

 the side of the tooth, to the exterior of which they are continued, in 

 the greater part of their course in a straight line, and nearly at a right 

 angle to that surface. This description applies to what I have termed the 

 primary curvature of the calcigerous tubes ; the secondary curvatures 

 that each tube exhibits throughout its whole course consist of 

 undulations, which are coarser, more angular, and less regular than 



