278 SUMMARY OF CURRENT RESEARCHES RELATING TO 



habit of swimming on their backs. Prof. G. B. Howes, in a review,* 

 notes that " the possibility that the maculae may have been luminous 

 organs must not be overlooked ; and bearing on this surmise, it is well 

 to remember that such organs are known to exist in a lenticulate and 

 aggregated form, and that the probable presence of one of t-imple type 

 in a sponge, taken in conjunction with the extent to which like organs 

 are functional as a lure to the prey, would dispose of any anomaly in 

 their possession by blind animals." Perhaps, as Howes suggests, the 

 maculae were only " aesthetes," as in Chiton, for their visual function is 

 not proved. 



Annulata. 



Spermatophores of Oligochseta/f — F. E. Beddard observes that these 

 may be arranged in two classes : — (1) Shorter spermatophores con- 

 sisting of a chitinous case enclosing a mass of spermatozoa, immobile, 

 attached to body externally, in Lumbricidae, Criodrilus, Alma, Bothrio- 

 neuron ; and (2) long spermatophores of more complicated structure, mo- 

 tile owing to the projection of the tails of the spermatozoa, found in the 

 spermathecae, in TubificidaB, and Polytoreutus. It appears from this that 

 the Limicoke and Terricolse cannot be distinguished by their spermato- 

 phores, both types occurring in both divisions. Beddard's discovery of 

 the spermatophores in Alma (which has no sperm athecae) supports the 

 view that the spermatophores are produced by the spermiducal glands 

 or by the glandular tissue surrounding the orifice of the sperm-ducts. 

 But he does not exclude the possibility that in some cases the sperma- 

 thecae may also assist. 



New Form of Spermatophore in an Earthworm.}— F. E. Beddard 

 has found in the spermathecal sac of the Eudrilid Stuldmannia a peculiar 

 form of spermatophore. There is a " head " like that in Tubifex, a long 

 " beak " open at the extremity ; this is followed by a circumferential 

 swelling, which is again succeeded by a narrow neck ; this in its turn 

 gradually widens until at the middle the spermatophore is large and 

 plump. The interior is a mass of uncompacted spermatozoa. The whole 

 of the spermatophore seems to be moulded in the spermathecal sac; 

 the material conies in part from the spermiducal gland and in part from 

 a breaking down of the abundant cells which line the spermathecal sac. 



In Lumbricidae (Criodrilus, &c.) the spermatophores are compact 

 cases, generally open at one end, and are found invariably attached to 

 the outside of the body in the neighbourhood of the reproductive orifices, 

 sometimes even slightly imbedded in the skin. In Tubifex, &c, the 

 spermatophores are long thin motile bodies found only in the sperma- 

 thecae. That of Stuldmannia is evidently somewhat intermediate between 

 the two other types. 



Atlantic Palolo. § — Prof. E. Ehlers discusses A. G. Mayer's || 

 interesting discovery of an Atlantic Palolo phenomenon like that of 

 iSamoa. It occurs at Loggerhead Key, one of the Tortugas Islands. 

 But the name which Mayer gave the worm (StaiirocepJialus gregaricus) 



* See Nature, Ixiii. (1901) pp. 585-6. 



t Zool. Anzeig., xxiv. (1901) pp. 220-3. \ Nature, lxiii. (1901) p. 515. 



§ Nachr. k. Ges. Wise. Gottingen, 1900, pp. 397-9. 



|| Cf. this Journal, 1900, p. 672. 



