NOTE ON TWO SPECIES OF CUCUMAKIA FROM I'LYMOUTII. 307 



while in sji. 2 they are so few as to appear arranged in a single zigzag 

 series ; also, in the latter species, the ijodia are less completely 

 retractile. The arborescent tentacles are very similar in both forms. 

 Tiie general body colour of .s/>, 1 is a dirty, brownish white ; while 

 in sj). 2 it is a pure milk white, excepting the tips of the^^of^^V^ which 

 are yellowish. Both species are absolutely without maculation. In ,9^;. 1 

 the neck and the bases of the tentacles are uniformly tinged a rich 

 purple-brown colour, with more or fewer scattered pigment granules 

 of an even darker colour. On the other hand, in sj). 2 these parts 

 are typically pale, although generally they are more or less dusted with 

 dark-coloured pigment granules, and sometimes, indeed, to such an 

 extent as to render the neck region quite dark ; but in such a case 

 the dark pigmentation is never diffuse, as it invariably is in sp. 1. The 

 interspaces between the anal pa pill ce are darkly pigmented in sp. 1, and 

 in sp. 2 the interior of the anal orifice is reddish or orange coloured. 

 A great difference is noticeable in tlie texture of the surface. In 

 sp. 1 the test, being densely crowded with spicules, is very tough 

 and coriaceous, and its surface is much wrinkled, while in sp. 2 the 

 surface of the body is extremely smooth and delicate, marked only 

 with transverse strife due to the encircling fibres of the superficial 

 muscle layer. 



The spicular (hposits, which are much more numerous in sjj. 1 than 

 they are in sp. 2, show considerable and characteristic differences. The 

 general body spicule in xp. 1 is typically lozenge-shaped, perforated 

 with four large foramina, and always bearing about twelve very 

 prominent nodules : in sp. 2 the corresponding spicule is invariably 

 a1)Solutely devoid of nodulation, and an additional foramen is typically 

 developed at each end of the long axis of the spicule, thus doing away 

 with the simple lozenge shape. The upper body spicules of the two 

 forms offer even greater diversity of structure : while in sp. 1 they are 

 numerous and campanulate in form, in .s/>. 2 they are quite typical 

 ' tables,' and, being few in number, are easily overlooked. The lateral 

 deposits of the podia in s^^. 1 have their foramina typically in a single 

 series, while in sp. 2 they are arranged in two or more parallel rows, or 

 with a group of three or four small foramina at each end of the spicule. 



Ileturning now to I)r. Norman's paper on Cucumaria Montagui, 

 Norman first briefly describes the external features of three spirit 

 specimens, which he terms specimens ' A,' ' B,' and ' C,' and which 

 with others had been collected for him by a local naturalist at Polperro, 

 a few miles west of Plymouth. He then goes on to give a very full and 

 remarkably lucid account of the spicules of each of these specimens 

 individually. Specimen 'A' is certainly an example of what we have 

 termed Cucumaria, .s^a 1 : the general body spicules, the campanulate 

 deposits, and those of the podia and tentacles being well described. 



