ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 623 



reaction, converted starch into dextrose, and oil into fatty acids ; 

 6 mgrms, of the tissue of the organ rendered 15 c.c. of milk trans- 

 parent in four hours. Moreover, the ferment, removed from the 

 organ, previously hardened by treatment with alcohol, by extraction 

 with glycerol and subsequent precipitation with alcohol, converted 

 starch into dextrose, and fibrin into leucine and tyrosine. The organ 

 contains neither glycoholic nor taurocholic acid nor glycogen ; it is 

 therefore evident that this so-called " liver " is a true pancreas. 



Artificial Fecundation of MoUusca.*— Mr. W. Patten has suc- 

 ceeded in the artificial fertilization of the ova of Haliotis and Patella ; 

 this experiment has not been previously performed on any mollusc. 

 Careful investigations were made in order to exclude the possibility 

 of there having been a previous internal fertilization ; the absence of 

 an albuminiparous gland and external sexual organs in these molluscs 

 appears to show that the ova undergo naturally an external fecun- 

 dation. 



Development of Generative Organs of Pulmonata.|— Herr J. 

 Brock finds that the generative organs of pulmonate gastropods begin 

 to be developed in the last stage of larval life ; just below the cutis 

 there is, on the right side and in front of the oesophageal ring, a fine 

 cord of cells with a distinct lumen. A little later there is distinct 

 evidence of the presence of a commencing hcrmaj)hrodite gland, and 

 it is found that it and the efferent organs are developed in one and the 

 same mesodermal blastema. Primordial ova appear very early. The 

 author is convinced that in the formation of the external generative 

 orifice the ectoderm does not take any share, by the formation of any 

 invagination. After the formation of the oviduct the vas deferens 

 appears ; after this there is growth, but for a time no new formation ; 

 then the receptaculum seminis appears in the form of a wide-necked 

 outgrowth of the genital atrium. The author was not able to follow 

 out the later stages, but he thinks it is clear that the simple condition 

 of the generative organs which is permanent in the Prosobranchiata 

 is passed through during the development of the Pulmouata. 



Microscopic Anatomy of Dentalium. J — Prof. H. Fol finds that the 

 epidermis of JJentalium is nothing more than a simple epithelium, the 

 characters of which vary in different regions ; at either extremity of 

 the tube formed by the mantle some of the cells are modified to form 

 a mass of very large glandular cells ; each of these is imbedded in 

 the sul'jacent dermal tissue and has a more or loss flask-shaped form, 

 and is filled by a granular secretion ; one of these unicellular glands 

 may be one hundred ti.nes as largo as the ordinary epidermic colls ; 

 they arc the chief agents in the formation of the shell. 



The nerve-ganglia are formed of a cortical grey and an internal 

 white substance ; the latter consists solely of novve-fibrils, without 

 any neuroglia ; the grey matter is made up of ganglionic cells which 



• Zool. Aiizoip., viii. (188.5) pp. 230-7. 



t Nachr. K. (iesell. Wjbs. (iottin;,'eii, 18S1, pp. 499-504. 



J C'ompttfi Bendim, c. (188.)) i>p. KJ.'iH-S, 



