52 



P.R. PUGH 



one from another to form a small gonodendron; female gonophores 

 contain two or more eggs. 



Remarks. In Pyrostephos vanhoeffeni, the triangular thrust block 

 is best seen on smaller nectophores. On larger, preserved ones it is 

 bent up dorsally (see also Discussion section). 



Genus BARGMANNIA Totton, 1954 



Diagnosis. Pyrostephids with distinctive elongate nectophores. 

 Mature nectophores with large, triangular thrust block; without 

 apical wedge-shaped processes; with extensive ventro-lateral wings. 

 Basic ridge pattern may be augmented by additional ridges branch- 

 ing from apico-laterals. Nectosac basically cylindrical; dorsal and 

 ventral radial canals straight; lateral radial canals arise separately, 

 but in close proximity, from the dorsal canal. Pneumatophore with- 

 out apical pore. 



Siphosome diffuse; devoid of fully formed dactylozooids. Bracts 

 specifically variable in shape. Each cormidium; with simple tenta- 

 cle-like structure attached to stem midway between successive 

 gastrozooids; with single gonodendron; with four bud-like struc- 

 tures (?vestigial dactylozooids) with sexually dimorphic arrangement. 

 Second tentacle and fifth bud occasionally present proximal to a 

 gastrozooid. 



REMARKS. The meso-lateral ridges on the nectophores, as referred 

 to in the above diagnosis, are homologous with the vertical lateral 



ridges, as defined by Pugh and Youngbluth (1988), found on the 

 nectophores of certain agalmatid species. In these latter species 

 these ridges run vertically, or slightly obliquely, between the apico- 

 and infra-lateral ridges, although they may not reach the latter. 

 However, in Bargmannia spp. their arrangement is strikingly differ- 

 ent in that they have a very oblique course; and it is the infra-lateral 

 ridges that may or may not join them basally. For these reasons the 

 term meso-lateral ridges will be used herein. 



In contrast, the outer of the two branches of the apico-lateral 

 ridges should not be compared with the lateral ridges of agalmatid 

 species, as defined by Pugh and Youngbluth (1988). They more 

 closely resemble the near-ostial branching of the apico-laterals in 

 agalmatid species such as Lychnagalma utricularia (Claus, 1879) 

 (see Pugh & Harbison, 1986) and Halistemma transliratum Pugh & 

 Youngbluth, 1988, which also possess normal lateral ridges. 



The long, median canal that runs up the thrust block (see Figure 

 2), just below its ventral surface, has been variously referred to as a 

 pallial (e.g. Daniel, 1974) or a pedicular canal (e.g. Daniel, 1985). In 

 accord with the definitions given by Totton ( 1 965 ) here the canal will 

 be referred to as the pallial canal; and the short canal, passing 

 through the mesogloea from the stem to the nectosac, the pedicular 

 canal. 



Recently, it has been brought to my attention (Dr S. Haddock, 

 personal communication) that the generic name Bargmannia was 

 used by Herre (1955) in a description of a genus of an extinct sala- 

 mander. Bargmannia Totton, 1954 clearly has priority of publication. 



Fig. 1 Bargmannia elongata. A. Photograph (reproduced by kind permission of Larry Madin, WHOI) of live specimen collected during Alvin Dive 961. 

 B. Photograph (reproduced by kind permission of Steve Haddock, UCSB) of live specimen collected during JSL I Dive 2673. Nectosomal length c. 9 cm. 



