10 ARKIV FÖR ZOOLOGI. BAND 13. N:0 3. 



Locality: West of Aden, 12° 35' N., 44° 39' E., 26 fa- 

 thoms. ( Vega-Exped. ) . 



I cannot find any remarkable difference in the general 

 habit ner in the arrangement and shape of the hydrothecae 

 between Halicornaria gracilicaulis and Lytocarpus Hornelli; so 

 for this reason I consider that these two hydroids can be looked 

 iipon as being forms of one and the same species. 



In my above-mentioned report I ha ve stated that Halicor- 

 naria gracilicaulis is to be found in South Japan. In reality 

 the place is situated in the China Sea (about 300 km. N. N. E. 

 of Formosa), 27° 35' N., 123° 35' E, 50 fathoms, ^y^, 1879. 

 In this locality the foUowing species are also found, namely: 

 Sertularella mirabilis, S. sinensis, Synthecium orihogonium, 

 Diphasia scalariformis, Monostoechas quadridens, Lytocarpus 

 pennariiiSy Halicornaria expansa and H. Vegae. Diphasia 

 scalariformis, Halicornaria expansa and Monostoechas quadri- 

 dens were also collected in 29° 20' N, 125° 40' E., 57 fathoms, 

 -7io 1879 (Vega-Exped.) 



