48 SUMMARY OF CURRENT RESEARCHES RELATING TO 



indicative of the collapse of the organism or arrest of the circulation, 

 and as occurring in cases where the muscular elements act in isola- 

 tion from the collective life. His theory of the phenomena is reserved 

 for a future paper. 



y. General.* 



Markings of Animals.f — Eimer has advanced the view that the 

 markings on animals are primitively longitudinal stripes, which may 

 subsequently be broken up to form dots, and these fuse to form 

 transverse rings. This view is supported by the ontogeny of many 

 animals. Dr. W. Haacke controverts this view from the study of an 

 Australian fish, Helotes scotus. The adult fish is marked by eight 

 longitudinal black bands ; young specimens have in addition a row 

 of clear transverse bands, which disappear when the fish attains to 

 maturity. 



B. INVERTEBRATA. 



Chromatology of Blood of Invertebrates. | — Dr. C. A. MacMunn 

 describes the spectroscopic or chemical characters of the blood of 

 various worms and molluscs ; one of the most interesting pigments 

 which he has detected is that which he calls echinochrome, and which 

 he has obtained from the perivisceral cavity of Strongylocentrotus 

 Iwidus ; the corpuscles present all degrees of coloration from a 

 brilliant lake red, through a pale orange, to colourless, and they 

 vary in having one or more nuclei. Echinochrome deepens on ex- 

 posure to air, and this seems to be at least partly due to oxidation ; 

 it is certainly capable of existing in two states of oxidation, and is 

 therefore respiratory; the author gives a detailed account of its 

 spectra and solubility, and states that he has not met with any 

 animal colouring matter which resembles it. 



Radial Disposition of Medusae and Ecliinodermata.§ — Dr. W. 



Haacke attempts to decide what ought to be regarded as the primitive 

 number of " segments " in radiate animals. Hackel regards the 

 Asterids as nearer to the primitive ancestors of the Echinodermata 

 than other groups, because in them there are species with varying 

 number of arms as well as species with a constant number, and that 

 a high one. On the other hand, the Echinoidea and Holothuroidea 

 exhibit no such variations. Dr. Haacke records the fact that in 

 Amhlypneusfes he has seen individuals with four and with six para- 

 meres; Hackel's views, therefore, cannot be considered as at all 

 trustworthy. According to the latter, the primitive number of 

 parameres in Medusae is four, and Dr. Haacke from his own re- 

 searches is inclined to agree. It is possible that four parameres and 

 not five are typical for the Echinodermata, but the question is as yet 

 an open one. 



* This section is limited to papers which, while relating to Vertebrata, 

 have a direct or indirect bearing on Invertebrata also, 

 t Zool. Anzeig., viii. (1885) pp. 507-8. 



j Quart, Journ. Micr. Sci., xxv. (1885) pp. 469-90 (2 spectroscopic charts), 

 § Zool. Anzeig., viii. (1885) pp. 505-7. 



