14 BULLETIN 93, UNITED STATES NATIONAL MUSEUM. 



Suborder LEPADOMORPHA. 



Usually riongatp and differentiated into capitulum and peduncle, the former pro- 

 tected by larger plates of specialized shapes, or sometimes all plates are wanting. 

 Mesozoic to Recent. 



Families: Loeiculid^ {Loricula, Arclixolcpas) , Brachylepadid^ (if distinct 



from SCALPELLIDiE), ScALPELLID^, LePADID^. 



Suborder VERRUCOMORPHA. 



Depressed, sessile, protected by an asymmetrical wall of four dissimilar plates 

 immovably articulated together — carina, rostrum, a tergum, and a scutum; some 

 lateral wall-plates are sometimes present on one side. The other tergum and scutum 

 form a movable lid closing the orifice. Mesozoic to Recent. 



Family: Verrucid^. 



Suborder BALANOMORPHA. 



Sessile, the wall bilaterally symmetrical, composed of carina, rostriim, and one to 

 three pairs of lateral compartments; opercular valvf s paired, furnished with depressor 

 muscles, or rarely wanting. IMesozoic to Recent. 



Families: Chthamalid.e, Balanid^e. 



The first two suborders have hitherto been grouped together as 

 Cirrij)edia Pedunculata; the last two as Ciirijiedia Operculata or Ses- 

 silia, with the divisions Asymmetrica and Symmetrica. The Pedun- 

 culata and Operculata of recent authors are exactly equivalent to the 

 groups Campylosomata and Acamptosomata of Leach.^ 



DESCRIPTIONS OF GENERA AND SPECIES. 

 Suborder VERRUCOMORPHA. 



Family VERRUCID.E Darwin. 



1825. Clisiadx Leach, Zoological Journal, vol. 2, p. 210. 



1854. Venucidse Darwin, Monograph on the subclass Cirripedia, etc., Balanidae, 



Verrucidte, etc., p. 495. 

 1914. Verrucidx Withers, Proc. Zool. Soc. London, ]i. 946. 



"Sessile, asymmetrical, boxlike barnacles, in which a scutum, ter- 

 gum, rostrum, and carina, with or without a rostral and a carinal 

 latus in addition, are immovably united to form the wall; the remain- 

 ing scutum and tergum are movable, and form the lidlike top" 

 (Withers). Basis membranous; caudal appendages present. La- 

 brum with a concave edge. 



Although the Verrucida3 are grouped as sessile barnacles, they 

 have no near relationship with the Balanidse. The family comprises 

 two genera: Verruca Sowerby (see below) and Proverruca Withers, 

 a Lower Devonian genus, "in which a rostral and a carinal latus are 

 present on the rostrocarinal side, and in which none of the valves 

 has developed interlocking ribs." ^ 



New light has been thrown on the phylogeny of Verrucidse by the 

 recent discovery of the Lower Devonian genus Proverruca and the 



» Zoological Journal, vol. 2, 1S25, pp. 208, 200. = Proc. Zool. Soc. London, lOlJ, p. 9-lG. 



