ZOOLOGY AND BOX AN Y^ MICROSCOPY, ETC. 153 



fragmentation of th^ skin are recognized, and that the conditions 

 inducing these may be paralleled in the conditions of hydroids occurring 

 in exposed rock-pools between the tide-marks of the tropics. " A closer 

 study of the histology of the pigmented tissue resulting from disease in 

 the higher animals would be of the greatest interest to compare with 

 that of the blackened hydroids, and there is no doubt that observations 

 on the pathology of simple organisms is capable of giving an important 

 insight into the fundamental causes and effects of diseases as found in 

 man and other mammals." J. A. T. 



Structure of New South African Hydroid. — Ernest "Warren 

 {Annals Natal Museum, 1919, 4, 1-18, 2 pis.). A description is given 

 of Bimeria rlgida sp. n., peculiar (1) in the simple nature of the hydro- 

 caulus ; (2) in the great development of the perisarc over the hydranth, 

 for it extends almost to the edge of the capitula of the elongated 

 tentacles, and over the whole of the hypostome region ; (3) in the 

 presence of a small ectoderm-chamber above the mouth, almost of the 

 nature of a stomodseum ; and (4) in the termination of the tentacles in 

 small, but perfectly distinct, capitula, with well-developed nematocysts. 

 This form shows the extreme type of protection by perisarc production 

 in the G-ymnoblastea, and this apparently has not proved a great success, 

 since the condition is rare or almost unique. Notwithstanding a kind 

 of calyx, there is not necessarily a step towards the true calyx of 

 Calyptoblastea, which is free from the body of the hydranth. J. A. T. 



New Species of Sertularella. — Armand Billard {Arch. Zool. 

 Exper., 1918, 58, Notes et Revue, 1, 18-25, 3 figs.). From the Siboga 

 collection nine new species of this Hydroid genus are described. 



J. A. T. 



Coelentera of Gunnerus. — Hjalmar Broch {K. Norske Viden Skab. 

 Selskabs Skrifter, 1918, 4, 1-17, 1 pi., 5 figs.). A useful account is 

 given of the Coelentera described by Bishop Johan Ernst Gunnerus 

 between 1761 and 1768, including Gorgonia resedaeforynis (= Primnoa 

 resedaeformis), Gorgonia flabelUformis (= Paramuricea placomus), Madre- 

 porapertusa (= Lophohelia prolifera), Madrepora virginea (= Stglaster 

 gemmascens), and so on. His figures and descriptions were far ahead of 

 his time. Broch declares in his Report on the Stylasteridse of the 

 Danish Ingolf Expedition that the drawings Gunnerus gave of Stglaster 

 gemmascens " are the best which have ever been given of the species." 



J. A. T. 



Species of Crawling Medusa from the Cape. — J. D. F. Gilchrist 

 {Quart. Journ. 3ficr. ScL, 1919, 63, 509-29, 1 pL). A description is 

 given of Cnidonema capensis g. et sp. n., which is found in fair abund- 

 ance at certain times and places at the Cape of Good Hope. The young 

 form is usually very active, exhibiting crawling or walking movements 

 by means of its tentacles. The older and mature individuals remain for 

 the most part stationary. The tentacles have a strong adhesive power, 

 and apart from their walking movements show a sudden jerking upwards. 

 The mouth is moved slowly over the substratum, but the tentacles may 



