of the Ilydroida of the Adriatic. 117 



error inevitable, by his strange neglect of the later literature 

 of his subject. ,He supplies us with a list of the authors, 

 ranging from Donati in 1750 to Grube in 1864, Avho have 

 concerned themselves specially with the fauna of the Adriatic; 

 but of English writers on the Hydrozoa none are cited of 

 later date than Johnston (1847) ; while there are but scanty 

 references to the Continental and other works published since 

 his time. 



It is impossible that any treatment of the Hydroida can be 

 satisfactory Avhich practically ignores the researches of Alder, 

 Allman, Busk, Streth ill Wright, and others in this country, 

 who have cast so much new light on this dej^artment of zoo- 

 logy. In the hope of adding to the value of Prof. Heller's 

 work, by supplying a few points that have escaped him, I 

 venture to submit his Catalogue of Hydroida to some critical 

 revision. 



The list is a small one for a district so fertile in other forms 

 of animal life, embracing only thirty-seven species, of which 

 twenty-three are included under the five genera into which 

 Prof. Heller divides the Sertularia and PlumuJaria of John- 

 ston. The most remarkable deficiency occurs in the Athecate 

 or Tubularian section, under which only four species are re- 

 corded. About eighty species have been described from the 

 British seas. It is highly improbable that this important 

 group is not largely represented in the Adriatic ; and I hope 

 that Prof. Heller may have the opportunity of continuing his 

 investigations, and giving us a more complete account of this 

 interesting portion of his subject. 



Of the four Athecate Hydroids included in the Catalogue, 

 one is recorded as the Coryne pusilla of Gaertner : this is an 

 obscure species, which it is hardly possible to identify with 

 certainty ; and there is nothing to indicate to what particular 

 form Prof. Heller applies the name. A considerable number 

 of species of Coryne and the allied genus Syncoryne are now 

 known, and to one of them Gaertner's name has been assigned ; 

 but, in the absence of all reference in the synonymy to later 

 authors, it is impossible to decide which of these the Adriatic 

 form may be. The brief account of it given by our author 

 does not help us ; for the characters which he ascribes to it 

 are almost exclusively generic. At present, therefore, we can 

 only affirm, generally, that one species of Corynoid at least is 

 a native of the Adriatic. 



The species included by Johnston in the old genus Sertu- 

 laria Prof. Heller ranges in two divisions, for one of which 

 he retains the latter name, and assigns to the other Lamou- 

 roux's name Dynamena. This arrangement, which is based 



