ANTHOMKDUS.K AMAI.TII.KA, I'KN \.\HI.\. -'.', 



spindle-shaped, as long as the depth of the bell-cavity. The hydroid is C.or\in<n [>hn uvifern, 

 found at Loppen Island, ahout 10 miles from Hammerfest, at a depth of about I fathom. 



Amalthaea vardoensis Loman. 

 Amahh<ta vardiitnsis, LOMAN, 1889, Tijdschr., Nederland. Dierk. Ver., Ser. 2, Dcel. 2, p. 271, teit-fig. 5, taf. 13, figs. 1-9, 15. 



Hydroid about 50 mm. high. The thin, transparent perisarc extends only over lower halt 

 of stem. The terminal polypite is sharply set off from the stem by a constriction at its base. 

 Nearly 50 large tentacles in basal circlet at wide base of polypite. Over 100 very short tapering 

 oral tentacles in 7 to 9 circlets. 16 to 20 peduncles arise in a circlet from the sides of the 

 polypite between the basal and oral tentacles. Each peduncle bears a number of medusa- 

 buds, which have 4 radial-canals and 4 equally developed, very short tentacle-bulbs. The 

 hydroid is translucent rose-colored. Found in Busse Sound at Vardri, 71 N. lat., Norway. 

 For details of histology, see Loman. 



Amalthaea (?) Hybocodon(?) januarii Steenstrup. 



Corymorpha januarii, STEENSTRUP, 1854, Vidensk. Meddcl. Nat. For. Kjbbenhavn, p. 46. SARS, 1861, Annals and Mag. Nat. 



Hist., vol. 8, p. 356. 

 Amalthtfa januarii, ALLMAN, 1871, Monog. Tubularian Hydroids, p. 394. HAECKEL, 1879, Syst. der Mi-JuM-n, p. 39. 



Described by Steenstrup from a single imperfect hydroid found in the harbor of Rio 

 Janeiro, Brazil. The hydrocaulus is about 150 mm. long and 8 mm. wide. About 80 tentacles 

 in the proximal circlet, and these are about 50 mm. long. The oral circlet was imperfect 

 and can not be described. There were about 40 branched peduncles above the basal circlet of 

 tentacles. These bear numerous medusa-buds having 4 equal tentacle-bulbs, but oblique 

 margins. The free medusae are unknown. 



Genus PENNARIA Oken, 1815. 



Pennaria (in part), OKEN, 1815, Lehrbuch der Naturgesch., Bd. I, p. 94. 



Pennaria (hydroid), GOLDFUSS, 1820, Handbuch der Zoologic, p. 89. 



Pennarin (medusa), MI/CRADY, 1857, Gymn. Charleston Harbor, p. 50. 



Pennaria + Halocordyle, ALLMAN, 1871, Monog. Tubul. Hydr., pp. 363, 368. 



Pennaria, AOASSIZ, L., 1861, Cont. Nat. Hist. U. S., vol. 4, p. 278. AC;ASSIZ, A., 1865, North Amer. Acal., p. 187. HARTLAUB, 



1907, Nordisches Plankton, Nr. 12, p. 72. PEEBLES, 1903, Archiv. Entwick.-mech., Bd. [4, p. 55 (regeneration). 

 Pennaria, AGASSIZ and MAYER, 1899, Bull. Mus. Comp. Zool. at Harvard Coll., vol. 32, p. 161 .--CLARKE, 1907, Mem. 



Museum Comp. Zool. Harvard Coll., vol. 35, p. 6. 

 GlobicfpSf AC.ASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 344. VANHOF* EN, 1891, Zool. An/eiger, p. 443. HAECKF.I , 1879, 



Syst. der Medusen, p. 39. 



Globicfps (hydroid), AVERS, 1852, Proc. Boston Soc. Nat. Hist., vol. 4, p. 193. 

 Rucorvne (hydroid), LEIDV, 1855, Journ. Acad. Nat. Sci. Phila., ser. 2, vol. 3, part. 2, p. I VI- plate 10, figs. 1-5. 



The type-species ot this genus is Pennaria ilistielia ot Goldfuss, 1820, from the Mediter- 

 ranean. Oken's "Pennaria" is wholly indefinite, including as it does Plumularia, Aglao- 

 phenia, etc. 



(JKNERIC CHARACTERS. 



Codonidae with 4 permanently rudimentary tentacles, which are reduced to mere basal 

 bulbs. The hydroid stock is a Pennaria. 



Medusae of the genus Pennaria may become mature, and discharge their genital products 

 while still attached to the hydroid, and at the same time other individual medusae from the 

 same stock may be set free in an immature state. Generally, however, the genital products are 

 discharged a few hours after the medusae are set free into the water. 



There is no generic difference between the medusae of Pennaria and medusae belonging 

 to the genus Amalthtsa, but their hydroids are different. The hydroid stock of Amalthaa 

 is Corvnifjrpha, and is closely related to the hvdroids of the medusa genera Hybocodon, St., n 

 strupia, and Ectopleura. The hydroid of the medusa genus Pennariti McCrady is Pennaria 

 Goldfuss (Globiceps Ayers). On account of this decided difference in their hydroids we 

 have separated Pennaria from Amaltheea = (Corymorpha\ for their apparent similarity is 

 only a case of parallelism. 



