586 SUMMARY OF CURRENT RESEARCHES RELATING TO 



much promptitude after a longer or shorter period of illumination.. 

 Frequently the lighting-up occurred in serial succession, beginning with 

 those at the head end and proceeding towards the tail, with rarely more 

 than one alight at a time. It took one to two seconds from start to 

 finish of the series of illuminations. Simultaneous luminescence of all 

 the photophores was never observed, but groups were sometimes seen 

 active at one time. After a night in captivity the power of luminescence 

 disappeared. 



A photophore consists of eight parts : — Lens, lens epithelium, 

 photogenous layer, basement membrane, reflector, pigment mantle, con- 

 nective tissue theca, and nerves. 



The lens is nothing more than a strongly-thickened area of the 

 transparent three-layered cuticle. Below it is the delicate epidermis, 

 not infrequently showing karyokinetic figures. Directly inside is the 

 relatively thick photogenous layer, with heemal spaces between the 

 photogenous cells. Not a few of the elements showed disintegration in 

 process. There is a thin but distinct basement membrane. The 

 " reflector " is not always present ; it is a plano-convex or somewhat 

 hemispherical body, made up of branching and anastomosing cells with 

 horizontally extended slit-like interspaces ; the cup-like pigment mantle 

 of a reddish colour, sending out proximally a number of long chromo- 

 rhyzae. The theca is simply a condensed layer of the general connective 

 tissue. The exact mode of innervation of the photophores was not 

 determined. 



Durban Malacostraca.* — T. S,. R. Stebbing reports on a collection 

 from Durban Bay. He describes in particular Penseus durbani sp. n. 

 and Sphseroma tvalkeri Stebbing. Attention is called to Borradaile's 

 note on the resemblance of Huenia proteus de Haan to a " leaf " of 

 Halameda ; the specimen from Durban was of the normal triangular 

 shape. The illustrations are very fine. 



Euphausids collected by the " Liguria." f — G. Colosi reports on the 

 species of Eaphausia, Pseudeuphausia, Tkysanopoda, Nematoscelis, and 

 Stylochet.ro n, collected by the Duke of the Abruzzi on his " Liguria " 

 voyage round the world. The following new species are described : — 

 E. uncinaia, E . patachonica, and *S'. armatum. 



Copepod Parasite of the Sprat.J — Marcel Baudouin discusses the 

 disease of the spiat {Glupea spratta) caused by a parasitic Copepod 

 {Leniseetikus sardinsc). In 1888 Joubin showed that this parasite 

 caused sub-cutaneous or intra-muscular abscesses in the sardine. 

 Baudouin shows that it may cause a kind of gangrene in the sprat. 

 What it does is not to be confused with the work of another parasite of 

 the sprat, Nerocila ajfiais. 



* Ann. Durban Museum, i. (1917) pp. 435-50 (2 pis.). 



I Publicazioni R. 1st. Stud. Sup. Firenze, ii. (1917) fasc. vii. pp. 165-202 (3 pis.).. 



X Comptes Rendus, clxv. (1917) pp. 410-11. 



