436 SUMMARY OF CURRENT RESEARCHES RELATING TO 



means of a wide-mouthed vertical net. This net acts so as to capture 

 animals living at different levels of the vertical column through which 

 it works. The results were remarkable as regards the new species obtained, 

 and notes regarding some of these are given, e.g. Hymenodora parva sp. n. 

 from a depth of 3000 metres, and Oplophorus Grimaldii sp. n., a mag- 

 nificent crustacean, from 2000 metres. 



Structure of Heart in Malacostraca.* — W. Gadzikiewicz has ex- 

 amined the heart in a large number of types, and finds it possesses an 

 inner muscularis and an outer adventitia. An endocardium is not present. 

 As an illustration, some details concerning Nebalia, one of the forms ex- 

 amined, may be given. Here the inner muscularis is differentiated into 

 muscle fibres lying close to one another, each having an independent 

 sheath. The fibrillae lie peripherally in the protoplasm of the fibres. 

 The blood corpuscles lie on the inner layer, blend with it, forming 

 irregular and often marked thickenings of the protoplasmic substance 

 (sarcolemma) of the muscle fibres. The outer envelope (adventitia) 

 consists in Nebalia of very large cells with gigantic nuclei ; in Gammarus 

 •dnd^Squilla it forms a cellular membrane. 



Structure and Development of Poecilasma aurantium.f — Kurt 

 Hoffendahl has made a study of this barnacle found on the crab Geryon 

 affinis by the German Deep Sea Expedition. The following are some of 

 his results. The basal joints of the attaching antennas are lost with the 

 bivalve shell, and do not contribute to the peduncle. The bivalve shell 

 is in close connection with the mantle by means of a strong insinking 

 of chitinous substance. All the muscles, except that closing the shell, 

 are striped. The pancreas is a modified portion of the stomach ; there 

 are no other stomachic glands, but there are noteworthy diverticula from 

 the oesophagus and from the stomach. The chitinous tube often found 

 in the stomach of Lepadidae is the isolated cuticle. The mantle-gland 

 and the cement-gland are closely connected ; their secretions pass out by 

 a common duct ; the mantle-gland is a larval cement-gland. The kidney 

 is a modified portion of the body-cavity, and retains its connection with 

 it. Nussbaum's " undefinierbare organ" is a salivary gland. Darwin's 

 "auditory organ " at the base of the first cirrus is in direct connection, 

 through the oviduct, with the ovary, which lies in the mantle. The 

 peculiar homogeneous mass in the widened terminal part of the oviduct 

 is a hardened secretion. The absence of heart and blood-vessels is 

 confirmed. 



Indian Ocean Paguroids.J — A. Alcock continues his study of the 

 Indian Decapod Crustacea in the Indian Museum. The new instalment 

 is an elaborate memoir on the Paguroidre, or Paguridea, a group which 

 includes four families, namely, Pylochelida?, Paguridaa, Ccenobitidaa, and 

 Lithodidaa. The author begins with an interesting chapter of general 

 observations on the Paguridea and with a discussion of their distribution. 

 Then follows the systematic account of the first three families named 



* Jeuaische Zeitschr., xxxix. (1904) pp. 203-34 (4 pis.). 

 t Zool. Jahrb., xx. (1904) pp. 363-98 (4 pis.). 



X Catalogue of the Indian Decapod Crustaceans in the Collection of the Indian 

 Museum, part ii. fasc. i. (Calcutta, 1905) 197 pp., 16 pis. 



