THE BURROWING BARNACLES (CIRRIPEDIA: ACROTHORACICA) 87 



The front of the cyprid is rounded. The entu-e carapace was stream- 

 lined, tapering posteriorly in both side and top view. 



Masses of granular and cellular material occupied the anterior half, 

 while the swimming setae occupied the posterior half. The latter 

 appeared typical of the order, and a small caudal furca was noted. 

 Typical antennules were present. 



Family CRYPTOPHIALIDAE GERSTAECKER, 1866-1879, 



page 534 



Diagnosis: JPygophora with alimentary canal with gut teeth (giz- 

 zard); mouth cirri atrophied or absent; large, attenuated labrum 

 present; mouthparts relatively weak; burrow aperture nearly round, 

 slightly tapered; three or four pairs of terminal cirri; no caudal ap- 

 pendage; lateral bars present; free cyprid larva only. 



In cryptophialids the mantle is laterally compressed and equipped 

 with an oval attachment disk. The body lies recurved in the mantle 

 sack, with a thick prosoma, and a long, thin, segmented terminal por- 

 tion (thorax). The three or four pairs of long, biramous, multiarticu- 

 lated thoracic cirri project up to the narrow aperture. Darwin (1854) 

 recognized eight thoracic and three abdominal segments in his descrip- 

 tion of C. minutus, while Berndt (1907a) described ten undefined 

 segments in the genus. It has been adequately pointed out by Gruvel 

 (1905) that the abdominal appendages are lost in the adult acrothor- 

 acicans, and hence the designation of abdominal appendages is in 

 error. 



The "mouth cirri" (Berndt) are unique among the Acrothoracica 

 in not being biramous. Darwin called these the "first pau" of maxilli- 

 peds," while Kriiger (1940) considers them to be modified, atrophied, 

 first cirri. The latter view I consider to be correct. The three or four 

 pairs of biramous thoracic cirri stand on two-segmented basal portions 

 (protopods). 



Genus Cryptophialus Darwin, 1854, page 563 



Diagnosis: Cryptophialidae with three pairs of terminal cirri; 

 two dorsal body processes present; mouth cirri rudimentary or 

 absent. 



Type-species: Cryptophialus minutus Darwin, 1854, page 563. 



