944 EECORD OF CURRENT RESEARCHES RELATING TO 



made up of very small cells, which are cubical in form and regular in 

 arrangement. 



Pentastomum polyzonum.* — Professor Jeffrey Bell has been able 

 to rediscover this species in an African python which died in Womb- 

 well's menagerie. The species was shortly described and well figured 

 by Dr. Harley in the ' Proceedings ' of the Zoological Society for 

 1857, the specimen being from the collection of Dr. Sharpey, but 

 having no history. A careful comparison of the two specimens in the 

 British Museum with Dr. Harley's figure, and an examination of 

 other species, seems to show that the number of the rings of the integu- 

 ment is pretty definite for each form ; P. polyzonum having nineteen 

 rings, and P. annulatum Baird (described by Harley under the name 

 of P. muUicinctum), having twenty-seven or twenty-eight. 



5. Crustacea. 



Anal Respiration of the Crustacea, t — In a former note J Mr. M. 

 Hartog suggested that the zoea larva of the higher Crustacea would, 

 on examination, prove to breathe in the same way as the Copepoda. 

 Zoeas of Cancer, and probably of some species of prawn, have con- 

 firmed this amply. The respiratory diastole and systole of the rectum 

 with rhythmical openings of the anus, are thoroughly well marked. 

 It may here be noted that in carmine stainings of the entire Copepoda 

 the stain does not diffuse through the integument, but up through the 

 rectum in the first instance. The power of dialysis through the 

 chitinized integument is slight, if at all existent. Now that another 

 place is found for the respiratory function, it may be denied to the 

 expanded pleura of the carapace. 



This constancy of function in the anus is remarkable, and indi- 

 cates that the gills which characterize so many of the higher Crustacea 

 are secondary formations, long posterior to the differentiation of the 

 class. As to their origin ? They are probably, in all cases, modifica- 

 tions of those processes of the appendages which primitively bring 

 about nutritive currents. 



Genealogy of the Mysid8e.§ — Herr Czernjawsky has given an 

 account of his speculations on this subject. He has been examining 

 thirty-two species, most of which are new, and has noted very remark- 

 able variations in the locomotor organs, and in the parts of the mouth, 

 as well as in the brood-cavity of the mother. He comes to the con- 

 clusion that the Mysidae form a side-branch of the great Crustacean 

 phylum, and that this branch began at the same point as that of the 

 Macrura, which, for its part, gave rise to the Brachyura and the 

 Anomura. The fact that the auditory organ of the Mysidae is placed 

 in the caudal appendages, and in the Macrura at the base of the 

 antennae, seems to prove to the author that the latter are not derived 

 from the former. 



* ' Ann. and Mag. Nat. Hist.,' vi. (1880) p. 173. 

 t ' Quart. Journ. Micr. Sci.,' xx. (1880) p. 485. 

 t See this Journal, ante, p. 633. 

 § 'Zool. Anzeig.,' iii. (1880) p. 213. 



