630 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
species which has been called erroneously Aristias tumidus and Lysianax 
andouinianus by different authors. 
Antennae of Cyclopidae.* — Prof. C. Claus shows how the prehensile 
17-jointed antennae of male Cyclopidae are derived from the 10-jointed 
appendages of the young, and that they are referable to the type seen 
in the females and in Calanidae. The distal portion of the prehensile 
antennae of Cyclopidae has the same number cf joints as the corresponding 
part in Calanidae, the geniculation occurs at a similar place, there are 
freshwater Calanidae approximating to the Cyclopidae, the youngest 
Cyclopid stage of Cyclops has rudiments of the antennary exopodite and 
2-jointed mandibular palps ; these and other facts corroborate a con- 
clusion based on a wider series of observations, that the Cyclopidae are 
simplified and retrogressive Copepods of the Calanid type, and that the 
Calanidae and Pontellidae are nearest the Protocopepoda. 
Herr Al. Mrazek j* has, independently, reached conclusions which 
are in the main similar to those of Prof. Claus, e. g. regarding the 
relations between Cyclopidae and Calanidae. 
Freshwater Harpacticidae.f — Herr Al. Mrazek gives an account of 
the forms which he has found in Bohemia. His investigations reveal 
an unsuspected abundance of species. Indeed, the family appears to 
have been somewhat neglected by systematists. In his general notes 
the author speaks of the resemblance to Harpacticidas exhibited by some 
species of Cyclops , e. g. C. fimbriatus, C. affinis , and C. phaleratus. This 
resemblance is the result of “ convergence,” i. e. of adaptation to similar 
conditions of life. 
Herr Mrazek’s systematic list is as follows : — 
Subfam. Longipediinae Boeck. 
Phyllognathopus paludosus g. et sp. n. 
„ Canthocamptinae Brady. 
Marsenobiotus vejdovskyi g. et sp. n. 
Epactophanes richardi g. et sp. n. 
Ophiocamptus g. n., two new species and 0. brevipes. 
Canthocamptus autt., four new species. 
Vermes, 
a. Annelida* 
Post-Larval Stage of Arenicola marina. § — Dr. W. B. Benham 
understands by “post-larval stage” that stage in the developmental 
history of Arenicola in which the full adult number of somites has 
appeared, and the body is divisible into an anterior chaetigerous region 
and a posterior achaetous region or tail, but in which the gills are not 
completely formed or have not made their appearance. The larvae, as 
obtained by Mr. Garstang, were found to be each inhabiting a per- 
fectly colourless and transparent gelatinous tube, obviously secreted 
by itself. This tube seemed to invest the body closely, and was cer- 
tainly no impediment to the animal. Each segment of the tail was 
found to be surrounded by a band of gland-cells, and these cells were in a 
* Zool. Anzeig., xvi. (1893) pp. 277-85. t Tom. cit., pp. 285-9. 
X Zool. Jahrb. (Abth. Syst., &c.), vii. (1893) pp. 89-130 (4 pis.). 
§ Journ. Mar. Biol. Ass., iii. (1893) pp. 48-53 (1 pi.). 
