6i 



few remarks of Pelseneer '), a stvidy by Peck ") on Cymbuliopsis calceoh, and a [jreliminary 

 note of Heath and Spaulding ■*) on Cymbuliopsis vitrca. About Glcba we know somethino- 

 more, especially after the researches of van Beneden *), Gegenbaur '") and Pelseneer "). 



As I have had an opportunity to examine some specimens of Glcba, brought home from the 

 Naples Station by Dr. Nierstrasz, I have been able to compare the results of my examinations 

 of Gleba with those, obtained from the study of Cymbuliopsis. Some specimens of this latter 

 genus were investigated by making a series of transverse sections. 



As no sufficiënt drawing of Gleba cordata exists, and in order to show the muscular 

 fibres in the fins, already alluded to, a figure is given on PI. IV, fig. 109. Fig. 110 represents 

 the shell. \\\ the small specimens, however, the shell bears no tubercles, and is perfectly smooth. 

 I may further remark, that the number of indentations is not always five, but varies in different 

 specimens from six to four. 



The palhal gland presents a similar aspect in both genera (PI. IV, figs. iii — 112). It 

 is somewhat asymmetrical, and three transverse bands divide the shield in four parts. The most 

 proximal of these bands («) is very narrow, the second {b) is the broadest and asymmetrical 

 while the most distal ie) does not divide the pallial gland over its whole breadth, as this 

 band does not reach the right side. In Cymbuliopsis as well as in Glcba the pallial gland is 

 twisted slightly to the left, contradictory to Peck, who described and figured the pallial gland 

 of Cymbuliopsis calccola, as twisted to the right. Neither radula, nor jaws or salivary glands 

 are found in each of the genera. The very long oesophagus is more markedly separated from 

 the stomach as in Cymbulia. In the stomach, situated quite dorsally and slighth' to the right 

 in the visceral nucleus, are found the same horny masticatory pieces as in Cymbulia.^ the fifth 

 plate being equally dorsal, as Peck stated already in the species, studied by him. xA coecum 

 could scarcely be indicated, and was even entirely absent in Cymbuliopsis. A little to the right of 

 the median line opens the liver with a very large opening. The liver occupies almost the whole 

 visceral nucleus, extending proximally even as far as the central nervous system, so that its 

 proximal end is interposed between the ganglia and the oesophagus. Immediately beneath the 

 hepatic opening a very thin intestine arises which takes its direction to the left side, and then 

 runs on at the dorsal side of the stomach to the right. Though the extreme portion of the 

 rectum is directed to the left, the anus does not reach the median line, and opens to the right 

 of it (PI. IV, fig. 113). 



The heart and the kidney are situated above the visceral mass. The kidney (PI. IV, 

 fig. 114, ö) has a semi-lunar shape, and at its concave side, towards the nucleus, is found the 

 heart [a). Both these organs are situated nearly in the median line, but the left lobe of the 

 kidney is slightly more developed than the right. The opening into the mantle-cavity is found 

 at the right side {d) \ it is represented in the figure in a contracted state. I have not found, 



:) Challengei- Report, LXVI, p. 26 — 27. 



2) Stud. Biol. Lab. J. Hopk. Univ., vol. IV, p. 335 — 353. 



3) Pi-oc. Ac. Nat. Sci. Philadelphia, vol. LUI (1901), p. 509 — 511. 



4) Acad. Roy. de Bruxelles, tome XII, p. 21 — 27, pi. II. 



5) Gegenbaur. Untersuchungen über Pteropoden und Heteropoden, p. 54 — 68. 



6) L. s. c, p. 27 — 28. 



