Phyllopoda of Australia. 239 



penis when lying within the lumen of the sheath becomes the 

 outermost, and each penis Ijecomes inflated with seminal fluid. 

 When one or both of the penes enter the ovisac it would seem on 

 structural grounds as if they were prevented from being with- 

 drawn in consequence of the large recurved spines, and must 

 perforce be left beliind after copulation. I have, however, never 

 found any remains of them in the ovisac bearing mature eggs. 

 When once the penes are everted, there do not appear to be 

 any muscles to enable them to be again introverted. 



2. Branchinella eyrensis, sp. nov. (Pi. XXXI.). 



Body of normal form, tail, exclusive of caudal rami, about 

 one-fourth shorter than the cephalon and trunk combined. 

 Caudal rami in the male as long as the four terminal 

 segments combined. Frontal appendages very long and ribbon- 

 like, extending much beyond the limit of the claspers, 

 united proximally for aljout one-third of their length and 

 bearing stout spines only. Claspers of normal form, second 

 joint evenly curving inwards, of similar length to first joint, 

 inner surface with very strongly marked transverse ridges. 

 Second antennae of f'-male apparently similar to those of B. 

 australiensis (incomplete in my specimens). 



Branchial feet with distal lobe of endopodite narrower and 

 longer than in B. australiensis, those of the middle area in 

 specimens of about 3.3 mm. in length, with the inner and outer 

 margins converging to a narrow apex, which is emarginated in 

 the middle. Gills subcircular in outline. 



Ovisac without any projecting lip or ridge on ventral surface. 

 Penes when everted from their sheaths of very great length, 

 extending as far back as the penultimate tail segment, normally 

 spin u lose. 



Leno^th. — Male, exclusive of caudal rami, 33 nnn. ; female a 

 little longer, but one specimen, locality unknown, fully 50 mm. 



Distribution.— ^i\X.^v holes, Upper Onkaringa Creek, Central 

 Australia (S.A. Museum, collected during Elder expedition, May, 

 1891). One female, Wintinoriua, near Lake Eyre (collected by 

 Mr. H. J. Grayson). 



Remarks. — Five specimens were received, and all of about 

 similar size. In general appearance they .are very like B. 



