532 DBS. H. C. SORBT AND W. A. HEEDMAN ON THE 



It seems probable that this species reproduces by gemmation, 

 as suggested by Forbes in 1853. The adult individuals give off 

 long branched stolon-like prolongations from the test near the 

 posterior end of the body ; and on these (the " root-fibres " of 

 Forbes), which form a matted mass by which the individuals are 

 united together into clumps, are found young specimens of diffe- 

 rent sizes. Further observations on the living animal in regard 

 to this point are much needed. 



POLTCAEPA POMAEIA, Sav. (?). 



Three specimens of a small Polycarpa, found sticking together 

 by their bases at Brightlingsea, in 2 fathoms, and one specimen 

 found at Portland in 3 fathoms, are referred with some doubt to 

 this apparently very common and polymorphic species, which in- 

 cludes Cynthia coriacea of Alder, Cynthia tuberom of Macgillivray, 

 Polycarpa varians of Heller, Styela poviaria of Traustedt, and, 

 possibly, Cynthia sulcatula and C. granulata of Alder. 



The shape of the Brightlingsea specimens is irregularly ovate 

 and rather depressed. The largest specimen is nearly | inch 

 broad (dorso-ventrally) and | inch wide, while it is only 2|- to 

 I inch long (antero-posteriorly). The other two specimens are 

 rather smaller, about ^ inch in the greatest extent. The Port- 

 land specimen is rather higher, being |- inch dorso-ventrally at 

 the posterior end, ^ inch antero-posteriorly, and | inch laterally. 

 They are all attached by a large flattened area at the posterior 

 end. The apertures are both placed on the wide anterior end, 

 moderately far apart ; they are sessile and inconspicuous in the 

 spirit-specimens. The surface of the test is rough and corrugated, 

 and slightly incrusted here and there with adhering foreign 

 bodies. The colour, after having been kept in spirit, is a dark 

 reddish brown, except the specimen from Portland, which is 

 greyish white. 



The test is thick and very tough, and white on section. The 

 mantle is strongly muscular, and is closely united to the inner 

 surface of the test. The branchial sac is elongated dorso-ven- 

 trally, and has four folds on each side. There are four or five 

 internal longitudinal bars on each side of a fold, and only two or 

 three in the interspace, where the meshes are transversely elon- 

 gated, and contain about eight stigmata each ; they are occasion- 

 ally divided by a narrow horizontal membrane. The tentacles are 

 simple, numerous, closely placed, and large and small alternately. 



The dorsal tubercle is nearly circular m outline, and has both 



