38 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. IIO 



give a four-rayed figure. Constrictor muscles attached on the points 

 of the folds are shown by Croneberg (1888) to surround the pharynx ; 

 lateral constrictor muscles are said to be present by Chamberlin 

 (1931), though they are not shown in his figure (E). Lateral dilator 

 muscles (dll) inserted on the side walls of the pharynx have their 

 origins on the lateral walls of the pedipalp coxae. Chamberlin makes 

 no mention of dorsal dilators, but Croneberg specifically says that a 

 group of fibers from the epistome ("basal part of the rostrum") goes 

 to the pharynx, as is shown in the diagram at F. The distribution of 

 most of the epistomal muscles on the preoral under surface of the 

 labrum is an unusual condition found only in the Chelonethida, but 

 it can be correlated with that in the Solpugida, in which a few of the 

 anterior fibers extend into the labrum (fig. 7 G), and is suggestive of 

 that in Mastigoproctus in which a large bundle of epistomal fibers 

 goes to the posterior end of the labrum (fig. 9 D, Ibrmcl). 



The chelonethid ingestion apparatus has no duplicate among other 

 arachnids, and no other even approaches it in structure. The taphro- 

 gnath might be likened to the lamina dorsalis of the food passage in 

 Thelyphonidae, but the lophognath is not comparable to the lamina 

 ventralis, and the sacklike chelonethid pharynx is quite distinct from 

 the preoral part of the feeding apparatus. The principal sucking 

 organ of the chelonethids would appear to be the preoral structure 

 formed of the taphrognath and the lophognath, rather than the rela- 

 tively small pharynx. A lifting of the taphrognath from the lopho- 

 gnath by a contraction of its dorsal muscles (fig. 12 F) would draw 

 the liquid food into the taphrognathic channel, where, by a reversal of 

 the action, it would be impelled back to the mouth to be sucked into 

 the pharynx. The food-conducting channel from the prey, however, 

 as Chamberlin notes, must be formed by the approximated laminae 

 of the pedipalp coxae and the distal part of the labrum (A). 



The Chelonethida are said to catch and kill their victims with the 

 pedipalp chelae, from which the prey is given to the chelicerae to be 

 held while feeding. Chamberlin (1931), in describing the feeding of 

 Chelifer fuscipes Banks on a small lepidopterous larva, says the active 

 caterpillar, grasped and tightly held in the chela, becomes motionless 

 in 30 seconds, and is then drawn up to the mouth parts and seized 

 by the chelicerae. In a few minutes the larva becomes much shrunken, 

 when a new hold is taken by the chelicerae and feeding resumed at 

 another point of attack. Schlottke (1933b), observing the feeding 

 of Chelifer cancroides L, on meal worms, notes th'St the sucking of 

 the larval juices is preceded by an inflation of the larva with a secre- 

 tion from the mouth of the chelonethid, which evidently liquefies the 



