356 PKOCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



either side of the rhachis, as a maximum. The innermost are low 

 with blunt tips. The teeth increase in size outwards : the first 

 5-6 are small, the rest rather large ; about the middle of the half row 

 are generally one or two teeth markedly taller than the rest. The one 

 or two outermost are thin and erect, but not tall. 



The stomach is not enclosed in the liver, and is laminated internally. 

 The central nervous system is as in Archidoris. The pedal ganglia are 

 round ; the cerebral and pleural divisions are not very distinctly 

 separated ; the buccal ganglia are elliptical, strongly granulated, and 

 united by a short commissure ; the gastro-oesophageal ganglia are 

 united to them by short connectives and irregularly globular. The 

 genitalia also seemed much as in Archidoris, and entirely without 

 armature. The upper part of the vas deferens is soft and much coiled ; 

 the lower part is straighter and muscular. The spermatotheca is large 

 and round ; the spermatocyst elongate. A distinct prostate was not 

 found, but its absence cannot be considered certain. 



I consider the type-specimen of Abraham's Doris vestita as un- 

 doubtedly the same species as the animal found by Mr. Valentine 

 in the Falkland Islands, and both of them as probably identical with 

 the Biaulula Sandiegensis, var. pallida of Bergh from Cape Delgada on 

 the east coast of Patagonia (Argentine Republic), 42° 24' S., 61° 38' W. 

 It seems to me, however, safer to treat the form provisionally as a new 

 species, and not as a mere variety. B. Sandicgensis is marked with 

 dark rings which are totally absent in the specimens from the Atlantic 

 side and the Straits of Magellan, and there may be other differences 

 of detail. The resemblance in the radula3 is striking, but I could not 

 demonstrate the existence of a large prostate,^ although the vas deferens 

 has a thick prostatic portion. But one specimen was old and the other 

 much hardened. 



The animals also agree in many details with Trippa (?) hispida^ 

 Bergh, from the coast of Chile (Bergh, Opisthobranchier der 

 Sammlung Plate, 1898, p. 52). In fact, they differ in hardly any 

 point except that they have no trace of a dorsal ridge. They even 

 seem to have glandular masses attached to the outer surface of the 

 tube leading into the buccal cavity, as figured by Bergh for T. Mspida 

 (I.e., pi. xxxi, fig. 1), but the state of preservation makes it impossible 

 to be sure of the character of these organs. The animal, which is 

 referred by Bergh to Trippa with a qviery, seems to me to be practically 

 a Biaulula with a median dorsal ridge. Much the same may be said 

 of Atagema (Gray, 1850). Bergh describes the back of A. carinata as 

 " ganz fein chagriniert," but Quoy & Gaimard say that it was 

 covered with " petits polls rudes," which they represent in their figure. 



Biaulula Capensis, Bergh, also seems in many ways an allied species. 



Staukodoeis Falklandica, n.sp. 

 One specimen obtained by Mr. Valentine and given me by the 

 Manchester University Museum. It is soft, almost globular, and as 



Also in these specimens the stomach seems to be external to the liver, whereas in 

 the tyjiical 1). Sandicgensis it is included in it. 



