456 SUMMARY OF CURRENT RESEARCHES RELATING TO 



are sunk in the ground, and the water of the springs rises up, and 

 running over the top spreads out over the ground, or runs off in 

 small streams. At one of these springs, which is near the edge of a 

 bank of Big Bone Creek, the water spreads over the ground toward 

 the bank over which it trickles. There is not enough of it to form a 

 stream, spread out thus and quickly absorbed in the ground as it is, 

 but it affords a fine place for the growth of a species of Oscillatoria, 

 which forms a tolerably thick mat upon the surface, and in which 

 T. fonticola lives in countless multitudes. All the species of TacM- 

 dius hitherto known live in the sea, or in brackish water connected 

 with it. Plow the creature found its way to its present habitat is, the 

 author considers, a mystery, but the water of all the springs is 

 strongly impregnated with common salt, iron, sulphur, and other 

 mineral ingredients in less quantity. Moreover, the animals were 

 never found in the " gums " themselves, but only in the puddles out- 

 side, which being warmed by the sun were, through evaporation, more 

 strongly saline. 



Diaptomus (?) Itentuchjensis n. sp. is white and transparent. The 

 abdomen of the male has five, that of the female only four segments. 

 Cephalothorax with five distinct segments, but when crushed under 

 pressure the head appears to divide into four segments. Length 

 from apex of head to end of terminal setfe, 1 • 5 mm. Antennte as 

 long as the body. The difference in the male and female abdomen 

 suggests a doubt whether it properly belongs to Diaptomus. 



Adriatic Crustaceans Parasitic on Fish.*— A. Valle enumerates 

 69 species belonging to the Entomostraca alone. He gives the 

 synonyms, and states on what species of fish each is found. The 

 abundance of these parasites may be inferred from the fact that in 

 250 out of 670 specimens of fish examined by the author himself, 

 crustacean parasites were found, representing 66 species ; i. e. 38 

 per cent, of all the fish were affected. A new species of Brachiella, 

 B. ohlonga, is mentioned as occurring below the pectoral fins of Mugil 

 ceplialus and M. saliens, and a new Philichthys, P. Bichiardi, has been 

 once found in a canal of the prseopercular bone of Box salpa. 



Vermes. 

 Development of Hermella alveolata.t — Dr. E. Horst describes 

 the ova of this Annelid as having a highly granular vitellus and large 

 germinal sj)ot ; on the entrance of the spermatozoa the vitellus shrinks 

 away from the investing membrane, and, owing to the concentration 

 of the granules of the deutoplasm, there is developed a transparent 

 perij^heral layer. As the spermatozoa penetrate the vitelline mem- 

 brane, a filament larger than the rest, and similar to the pseudopodium 

 of an amoeba, advances from the yolk to meet a spermatozoon. After 

 about twenty minutes the two become fused, and the vitelline process 

 contracting carries the fertilizing element into the yolk. About an 

 hour later the yolk becomes flattened at one pole, at which the " polar 

 globules " soon appear ; the egg then commences to divide. 



* Boll Soc. Adriat. Sci. Nat., vi. (1880) pp. 55-81. 

 t Bull. 8ci. Dep. du Nord, iv. (1881) pp. 1-4. 



