258 RECORD or current researches relating to 



closely placed to one another that they almost seem to be fused. The 

 seminal duct after passing some way backwards returns upon itself, 

 and then bending outwards passes into a looped outer portion ; at the 

 lowest part of its course it has connected with it the so-called pouch 

 of the spermatophore ; it then narrows, and opens by an elongated 

 cleft at the side of the abdomen. 



As to histological details : there are three kinds of gland-cells 

 in the unicellular glands which are so common in this creature; 

 the first, which are found in the matrix of the whole body, 

 and are especially numerous in its lobes and projections, are of a 

 considerable size, invested by a strong membrane, while the distinct 

 nucleus is surrounded by a highly granular plasma, in which a mass, 

 apparently the result of secretion, may frequently be found ; the duct 

 of the gland has a funnel-shaped orifice through which it passes to 

 the delicate duct which traverses the carapace. These are the tegu- 

 mentary glands. The second set is not so numerously represented or 

 so widely distributed as the first; they are found on the lateral 

 margin of the dorsal lobes of the female, either singly or in pairs ; 

 the cells have clear, highly refractive contents, and the nucleus is 

 small. The third set of glands are found in the cephalothoracic 

 region, and are of great size ; the granulated contents are not all 

 similar, for large granules may be seen in the finer ground substance, 

 and the nucleus, which is very large, is especially remarkable for 

 being broken up into a number of pyramidal pieces, which are set in 

 the fashion of a rosette. Although the author was enabled to detect 

 the efferent duct, he did not succeed in tracing it through the whole 

 of its course. The lobes already referred to contain a distinctive 

 form of tissue; in addition to the ordinary connective tissue, there 

 are supporting fibres which appear to add to the consistency, and to 

 increase the elasticity of the structures in question ; further investi- 

 gations require to be made before their essential characters can be 

 said to be known. 



The young larvro escape from the egg in the Nauplius stage. 

 The genus is remarkable for the fusion of the first thoracic ring 

 with the cephalothorax, for the fusion of the remaining thoracic 

 segments into one piece, and for the diminished size of the posterior 

 locomotor feet and of the abdomen. The species differ from one 

 another in the characters of the lobate appendages of the body, and 

 in the relation of the various parts of the body to one another ; the 

 greatest differences in form are to be found in the females. Nine- 

 teen species are known ; in eighteen cases the female, and in ten the 

 male has been observed ; the author gives a key to these, which is 

 followed by an account of each ; his own researches do not appear to 

 have resulted in the discovery of any new forms. 



Red-Blood Vascular System of certain Crustacea.* — In connection 

 with the preceding note, Professor E, van Beneden states that he first 

 made some observations on this subject so long ago as 1868 ; he then 

 found that when the foliaceous organs (lobes of Heider) are carefully 



* ' Zool. Anzeiger.' iii. (1880) p. 35. 



