490 MEDUS.E OF THEjwORLD. 



Perigonimus vagans Thornely. 

 Perigonimus vagans, Thornely, 1908, Journal Linnean Soc. London, Zool., vol. 31, p. 81, plate 9, fig. I. 



Colony much branched, 35 mm. high. Branches alternate in origin, but inclining all 

 to one side, narrower than the main stem and narrowest at base where there are a few corru- 

 gations. Perisarc covered with sand. Some small polypites with few tentacles, some larger 

 on longer stalks with about 25 tentacles. Both sizes carry gonophores. Each gonosome 

 contains a single medusa. Khor Shinab, Sudanese Red Sea, 10 to 12 fathoms. Free medusa 



unknown. 



Stomotoca octaedra (see page in). 



Amphinema austral is, Bigelow, H. B., 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37, p. 199. P ,ates 7 and 3*- 



Bigelow separates Amphinema from Stomotoca on the ground that the former lacks a gelati- 

 nous peduncle while this is found in Stomotoca. In life, however, the peduncle of Stomotoca 

 pterophylla varies greatly in size, dependent upon the state of contraction of the medusa. 

 When contracted it is prominent but when the bell is fully expanded it becomes so broad 

 and flat as to be nearly indistinguishable. It would appear tome, therefore, to constitute a 

 somewhat uncertain character upon which to base generic distinctions. 



Bigelow has found many specimens of S. "australis," which I suspect is identical with 

 S. octaedra, in Acapulco Harbor, Pacific coast of Mexico on the surface. It was previously 

 known only from the Atlantic. Bigelow finds that the 4 gonads are interradial, with smooth, 

 external surfaces. 



Stomotoca divisa Maas (see page 114). 

 Stomotoca divisa, Bigelow, H. B., 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37, p. 203, plates 7 and 43. 



Bigelow finds that the gonads originate as interradial, horse-shoe-shaped swellings on 

 the sides of the manubrium but that later the interradial connections disappear and we find 

 8 adradial gonads entirely separated in both perradii and interradii. I find that the gonads 

 of Stomotoca pterophylla go through the same developmental stages (plate 29, fig. 4). Bigelow's 

 specimens were from Acapulco and from the Galapagos Islands, tropical Pacific. 



Dissonema turrida Mayer (see page 116). 

 Amphinema turrida, Bigelow, H. B., 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37, p. 200, plates 7, 4°. 43- ™ A 44- 



Bigelow found four specimens of this medusa upon the surface in Acapulco Harbor, 

 Pacific 'coast of Mexico. He has discovered that the gonads originate as 4 interradial, horse- 

 shoe-shaped bodies upon the sides of the manubrium and resemble those of Pandea and 

 Turris with definite, transverse folds. Later the perradial walls of the manubrium grow 

 outward along the radial-canals and thus the gonads come secondarily to lie along the radial- 

 canals as well as on the interradii of the manubrium. He therefore corrects Mayer's erroneous 

 account of 1900. Bigelow thus demonstrates that this genus is closely related to Stomotoca 

 and indeed he prefers to consider it as an Amphinema. As he states, it may prove to be 

 identical with Haeckel's Codonorclus octaedrus, and if this be true Stomotoca australis is a 

 distinct species (see page III). 



Dendroclava dohrni (see page 117). 

 Dendrodava dohrni, Goette, 1907, Zeit. fur wissen. Zool., Bd. 87, p. 42, taf. 4, fign. 78-84. 



The egg cells of Dendroclava first appear in the ectoderm of the inner part of the bell- 

 cavitv which later becomes the outer epithelium of the manubrium. The gonads are found 

 in 4 interradial, swollen regions of the ectoderm of the manubrium. 



Zoja, 1892 (Annals and Mag. Nat. Hist., ser. 6, vol. 9, p. 409), who describes the appear- 

 ance and habits of the living hydroid, concludes that it is probably related to Turns. 



Pandea violacea Agassiz and Mayer (see page 119). 

 Pandea violacea, Bigelow, H. B., i 9 c 9 , Mem. Mus. Comp. Zool. at Harvard College, vol. 37, p. 205, page 41, figs. 10, 11. 



Bigelow found seven specimens on the surface in Acapulco Harbor, Pacific coast of 

 Mexico. None of his specimens was more than 4 mm. high, and had only 8 well-developed 

 and 8 small tentacles. Bigelow corrects Mayer's account of the gonads for he finds that they 



