ZOOLOGY 225 



Invertebrate Morphology (excluding Entomology). — J. 

 Stephenson continues his series of papers entitled " Contribu- 

 tions to the Morphology, Classification, and Zoogeography of 

 Indian Oligochseta " in the Proa. Zoological Society (Pt. I, 

 1922). Part IV deals with the diffuse production of sexual 

 cells in a species of chsetogaster (Fam. Naididae), and in 

 Part V is given an account of the anatomy of Drawida japonicus, 

 one of the Moniligastridae, special attention being devoted to 

 the nephridia and genital organs. The sixth part is " On the 

 Relationships of the Genera of Moniligastridae ; with some 

 Considerations on the Origin of Terrestrial Oligochaeta." The 

 writer criticises the view that the Phreoryctidae, with five 

 pairs of gonads and oesophageal gizzard, are the present-day 

 representatives of the common ancestor. In the light of recent 

 research he contends they are too speciahsed, and the discovery 

 of Syngenodrilus points to the ancestral form having no oesopha- 

 geal gizzard and a large number of gonads. The Lumbriculidae 

 more nearly resemble this type than the Phreoryctidae. 



The method of determining the number of segments of the 

 Arthropoda, by counting from the anterior end of the body, is 

 criticised by A. Petrunkevitch (" The Circulatory System 

 and Segmentation in Arachnida," Journ. of Morph., vol. xxxvi, 

 No. 2, March 1922). In the case of the Arachnida, he suggests 

 starting from the cardio-aortic valve, which marks the division 

 line between the last thoracic and first abdominal segments. 

 Applying this method to Limulus, he finds that the carapace 

 is more complicated than in Arachnida, " having two abdominal 

 tergites drawn into the horseshoe-shaped thoracic tergite, 

 with which they have fused anteriorly and laterally." Adult 

 Arachnida have seventeen post-oral somites, five thoracic and 

 twelve abdominal, and the genital opening is on the second 

 abdominal somite. 



Other papers include : 



Stephenson, T. A., " On the Classification of the Actiniaria, Part III," 



Q.J. M.S., vol. Ixvi, No. 261. 

 Sherriffs, W. R., " Evolution within the Genus Dendronephthya (Spon- 



godes) (Alcyonaria), with descriptions ot a number of Species," Proc. 



Z.S., Part I, 1922. 

 YoKOGAWA, Sad AMU, " The Development of Heligmosomum muris, Yoko- 



gawa, a Nematode from the Intestine of the Wild Rat," Parasit., 



vol. xiv. No. 2. 

 Stolte, Hans- Ad am, " Experimen telle Untersuchungen iiber die unge- 



schlechtUche Fortpflanzung der Naiden," Zool. Jahr., Bd. 39, Heft 2. 

 Bahl, K. N., " On the Development of the Enteronephric Type of Nephridial 



System found in Indian Earthworms of the Genus Pheretima," Q.J. M.S.. 



vol. Ixvi, No. 262. 

 Cannon, H. G., " On the Labral Glands of a Cladoceran {Simocephaliis 



vetulus), with a Description of its Mode of Feeding," Q.J. M.S., vol. Ixvi, 



No, 262. 



