Nr. 1] ANATOMICAL STUDIES ON ANELASMA A ND SCALPELLUM 9 



used in analogy with other cases amoiig the cirripeds, as a designa- 

 tion of the exceptionally richly foldad, and consequently a little 

 swollen connecting part, where the cuticle of the oesophagal part 

 yet lines the epithelium, and where, on the other hand, the muscles 

 have faded away or are at all events only very feebly developed. In 

 reality the stomach of Anelasma can only be made out on acoount 

 of its deeply folded walls, which (pl. I, fig. 2 s.) give it a somewhat 

 swollen appearaiice; it is yet furnished with muscles, although 

 these muscles are only feebly developed in comparison with the 

 oesophagus proper, and especially the dilatatory muscles. The 

 boundary between the stomach and the digestive intestine is on the 

 other hand very distinct (pl. I, fig. 5), the cuticle of both regions 

 being principally different. 



The digestive intestine is covered by a cylindric epi- 

 thelium with distinct basal membrane (pl. I, fig. 6, pl. V, fig. 22). 

 Each epithelial cell is furnished with a finely striped distal zone; 

 the boundaries batween the cells are generally invisible in these 

 distal parts, and the striped zone mentioned therefore secms to form 

 a continuous la} r er or cuticle on the surface of the epithelium. In 

 its affinity to staining substanceis this cuticle differs strikingly from 

 the cuticle of the stomach, oesophagus, and proctodæum, the latter 

 attaining a clear blue colour after staining with boriaxcarmine- 

 bleu de Lyon, whereas the intestinal «cuticle», like nnost protoplasmat- 

 ic substances, assumes a violet hue; the fine stripes perpiendicular 

 to the surface are distinctly se en in all sections of the intestine. 



The protoplasrn of the intestinal epithelial cells is finely granul- 

 ated. The nuclei are generally situated in the middle of the cells; 

 they are provided with one, or iseldom two nucleoli, but other chro- 

 matic substances seem to fail almost completely. In other words, 

 the intestinal cells convey the impression of resting cells, a fact 

 probably dependant on the constant absence of nutritive particles 

 in the intestines of the individuals investigated. Even in a small 

 specimen, the tree part of which had a height of 1,5 mm. above the 

 skin of the shark, the nuclei of the intestine only showed traces of 

 chromatic network bes ide the nucleoli, a rather interesting feature 

 when tåken together with the features of the digestive glands stated 

 below. — The intestine is destitute of muscles. 



The proctodæum is distinctly bounded towards the intest- 

 ine (pl. I, fig. 2). Its very low cylmdmcal or almost cubical epithel- 

 ium is richly furnished with blackish grains of pigment in the basal 

 parts of the cells, and moreover covered by a rather thick homo- 

 geneous cuticle (pl. II, fig. 7), the direct continuation of the thoracic 

 cuticle. Here as elsewhere the cuticle exhibits a pronounced affinity 

 to bleu de Lyon, attaining a clear blue colour. The muscles of the 

 proctodæum are rather diffuse, and only more richly developed at 



