THE BURROWING BARNACLES (CIRRIPEDIA: ACROTHORACICA) 121 



and have a long apodeme. The second maxillae are typical of the order. 



The esophagus leads dorsally to a gizzard typical of the family, 

 with a toothed grinding mill anteriorly and what appears to be a fine 

 strainer posteriorly. 



A pair of small but obvious unsegmented, uniramous mouth cirri 

 are found on the ventral thorax posterior to the mouth field. 



A single dorsal body process was seen dorsal to the free portion of 

 the thorax. Although it is possible that a second one escaped my 

 notice in the two of the three specimens dissected which would show 

 this feature clearly, I believe that a single process is aU that is present. 

 It is thin walled and ^vrinkled, but not hairy or scaly as in other 

 species of the family. 



The posterior thorax is striated superficially. It bears at the pos- 

 terior extremity four pairs of biramous, multisegmented terminal cirri. 

 The posterior pair is tucked between the others (depending on the 

 angle of view) so that the superficial impression of three pairs is strong 

 (fig. 32) . The two-segmented protopod on each terminal cirrus is short, 

 with the two segments of approximately equal length divided by a 

 slanting suture. A small fringe of scaly hairs is found at the distal end 

 of the protopods, extending over the bases of the rami. 



The segment count for one specimen gave 5 and 13 for the anterior 

 and posterior ramus of the first terminal cirrus, and 19 to 25 for each 

 ramus of the others. Although no high degree of certainty could be 

 obtained with the few specimens, the count seems comparable with 

 other species in the family. 



The setation of the terminal cirral segments is typical of the family. 

 A pair of medial and distal setae, each about three times the segment 

 length, arise from each segment along the inner curvature of each 

 ramus, and a single seta about twice the segment length arises distally 

 on the outer curvature, up to four segments apart. The inner curv- 

 ature of the cirrus is wavy, in side view, with bosses for both the medial 

 and distal setae. 



No male was seen. 



Relationships: In proximity and anatomy this species is probably 

 closest associated with Australophialus turbonis, of known species. It 

 differs most noticeably in the opercular margin, which is not notched 

 or indented in this species. 



Australophialus turbonis (Barnard), 1925, page 5 



Figure 33 



Diagnosis: Australophialus with apertural margin bearing distinct 

 notch at about one-third the distance from the rostral (attachment) 

 end, margin lined with numerous short spines and hairs. 



