1830.] NATURAL SCIENCES OF PHILADELPHIA. St 



ated. In the skin a rather large quantity of spicula. The broad 

 centres of the warts of the back chalk-white in transverse section, on 

 account of the mass of strong spicula which ascend in bundles through 

 the axes of the warts, their peripheral parts being free from spicula. 

 The spicula, for the most part, staff-shaped or cruciate, reaching a 

 diameter of about 0.08 mm. ; small and large rounded ones were 

 also very common ; the spicula mostly very strongly calcified. In the 

 interstitial tissue calcified cells were seen scantily. 



The mouth-tube was 1.5 mm. long ; the bulbus pharyngeus about 

 I. .5 mm. long, the sheath of the radula projecting about 75 mm., 

 bent upwards ; the sucking-crop nearly as large as the proper bulbus, 

 short-stalked. The Hp-disk with the cuticula rather thick, especially 

 at the inferior median line, here sometimes prominent and reminding 

 one of the two blades in the AcantJwdorides. The tongue (in the six 

 individuals examined) with seven to nine rows of teeth ; further back- 

 wards twenty-nine, thirty-one, or thirty-four (in three individuals) 

 developed, and three younger rows ; the total number of rows was 

 thus forty-two to forty-six. The median plates (fig. 8a) and the large 

 lateral (fig. 6«a, Y, 86) ones quite as in the Ad. Pac'fica, also the ex- 

 ternal ones (fig. 6 J, 8c), but the number of those never surpassed ten 

 or twelve ;^ frequently all gone from the tongue, and only existing in 

 the two to four posterior rows ; the height of the large lateral plates 

 rising to about 0.09 mm. 



The salivary glands, as usual, white. The oesophagus somewhat 

 wider in its first part ; the stomach as usual ; the liver of usual form, 

 its substance of yellow color ; on the first quarter of the right side an 

 impression for the anterior genital mass. The vesica fellea rather 

 smaller, on the right side of and a little behind the pyloric part of the 

 intestine, with its upper end appearing on the surface of the liver ; 

 the duct nearly as long as the bag, opening in the stomach. 



The sanguineous gland of subquadratic form, the largest diameter 

 about 2.3 mm., very much flattened, whitish. The tube on the floor 

 of the renal chamber rather strong. 



The hermaphroditic gland clothing the liver with a thin, whitish- 

 gray layer. The anterior genital mass small, nearly undeveloped, 

 much compressed, of about 1.75 mm. in length, the height a little less. 

 The ampulla of the hermaphroditic gland thin, otherwise as usual. 



' According to Friele and Hansen (1. c. p. 3) the number of external 

 plates is twelve ; the figure of these authors (Tab, II, fig. 1) is rather bad. 

 G. O. Sars has eleven to twelve external plates in his figure. 



