696 REPORT— 1894, 



6. Such fieptatlon may have taken place repeatedly in the same line of descent. 



7. The sporogonial head as a whole is the correlative of the strobilus or 

 flower, and the apex of the one corresponds to the apex of the other. 



8. The progression from the one to the other depended upon (a) septation by 

 formation of sterile partitions, (b) eruption of the surface to form appendicular 

 organs upon -which the sporangia are supported (sporangiophores, sporophylls). 



9. The sporophylls, originally small and of simple form, were in the course of 

 descent susceptible of great increase in size and complexity of form. 



10. In certain cases foliage leaves were derived from sterilisation of sporo- 

 phylls. 



4. On a Method of Taking Casts of the Interiors of Flowers. 

 By Miss N. F. Layard. 



5. On the Function of the Nucleus. By Professor E, Zacharias. 



6. Exhibition of Diagrains. .5;/ Professor L^So Errera. 



TUESDAY, AUGUST 14. 

 Department op Zoology. 

 The following Papers were read : — 



1. On the Blood o/Magelona. By "W. B. Benham, D.Sc. 



The blood of this annelid diflers entirely from that of any other chretopod 

 hitherto examined. Instead of a red (hff:moglobinous) liquid plasma, in which 

 float a few nucleated (colourless) corpuscles, or free nuclei, the blood-vessels of 

 Magelona are completely filled with very small spherical globules of a madder-pink 

 colour, floating in an extremely small amount of colourless plasma. These globules 

 are not cells ; there are free nuclei scattered amongst them, but the coloured 

 globules are not nucleated. The colour of the globules is due to a pigment similar 

 to hsemerythrin ; the globules themselves, when shed, exhibit a marked tendency 

 to run together like oil-drops and fuse with one another. This peculiar and 

 rather viscous mass seems to be intermediate, in some respects, between the abso- 

 lutely liquid, coloured plasma of chsetopods generally and the red corpuscles of 

 mammals, which float in a comparatively small amount of colourless plasma; 

 further, the globules in Magelona probably originate, as those of- mammals do, 

 within cells, from which they are released. 



2. Suggestions for a New Classification of the Polychseta. 

 By W. B. Benham, D.Sc. 



The PolychcBta may be divided into two grades — (a) the Eucephala, in which 

 the prostomium retains its original condition as a lobe overhanging the mouth, 

 and the peristomium shows no tendency to overgrow it. The body segments are 

 all alike. The second grade (6) may be called Cryptocephala, as the peristomium 

 grows forward and fuses with, or even entirely conceals, the prostomium, which is 

 greatly reduced. The body segments are diflierentiated into two groups, indicated 

 externally by the sudden alteration of the chfetfe, and internally by certain 

 diflerences. 



The JEucephala includes four sub-orders : — 



Sub-order 1. The Nereidiformia ( = Errantia, auct.) together with Ariciidm. — In 

 this group, with a few exceptions, the prostomium carries tentacles and palps, and 



