58 AMERICAN HYDROIDS. 



iiiteruode, making four, or at most six, interuodes to each hydrocladium. Hydrotheca; shallow, 

 cup-shaped; supracalycine iiematophores sometimes \vautiug; a mesial netnatophore below the 

 base of each hydrotheca and one on the longer intermediate interuodes. 1 



Gonosome. Gouangia large, cyathiform. 



Distribution. Pacific Ocean, west coast of South America. 



The first specimens of this species examined by Kirchenpauer had but a single hydrotheca to 

 each hydrocladium. He afterwards found others with two and three hydrotheca- and intermediate 

 iuternodes, and made three subspecies of them based on the possession of one, two, or three hydro- 

 theca; to each hydrocladium. It seems altogether possible that these are simply individual pecu- 

 liarities which indicate different stages in the growth of the colony. This species must not be 

 confounded with that belonging to the genus Monotheca, which has but one hydrotheca to each 

 hydrocladium, but has also the thickened or forked internode supporting the very conspicuous 

 supracalycine uematophores. 



PLUMULARIA ALTITHECA, new species 

 (Plate II, lig. 1.) 



Trophosome. Colony attaining a aeiglit of 2 inches, consisting of a tuft of simple pinnate 

 stems; stem not fascicled, divided into regular iuternodes, each bearing a hydrocladium on a 

 process from its distal end; hydrocladia alternate, two or three short proximal interuodes without 

 hydrotheca-, then a long hydrothecate iuteruode, the remainder of the hydrocladium being made 

 up of alternating intermediate and hydrothecate iuternodes, the latter being somewhat the 

 longer. Hydrothecib distant, shallow, cup-shaped, much wider than deep, borne near the distal 

 ends of the iuternodes; uematophores almost entirely wanting in the specimen examined, although 

 the points of attachment for them are occasionally indicated. 



Gononoine. Gouangia ovate, pediculate, borue ou the hydrocladia at the bases of the 

 hydrotheca'. 



Distribution. Albatross Station 2671, lat. N. 31 20', long. W. 79 22', 280 fathoms; Albatross 

 Station 2666, lat. N. 30 47' 30", long. W. 79 49', 270 fathoms. 



This species resembles P. attenuata, with the distal part of each hydrocladial internode 

 separated from the basal portion by a distinct node. The processes from the stem are not so 

 large as usual in this group and there is no prominence on the upper part of the process. 



Type slides: 2 Cat. Nos. 18594, 18595, 18596, U.S.N.M.; Cat. Nos. 11733, 11734, 11735, Mus. 

 State Univ. Iowa. Also in collection of the author. 



PLUMULARIA FILICULA Allman. 



(Plate II, fig. 2.) 

 Flumului-iaJilicuJa ALLMAN, Mem. Mus. Comp. Zool., 1877, V, No. 2, p. 29, pi. XVIII. 



Trophoxome. Colony attaining a height of about 2 inches, usually unbranched; stem uot 

 fascicled and divided into iuternodes, each bearing a hydrocladium on a process from its distal 

 end; hydrocladia alternate, proximal iuteruode short, without hydrotheca, next iuternode hydro- 

 thecate, the remainder of the hydrocladium being composed of alternate intermediate aud 

 hydrothecate iuternodes, the former being slightly shorter. Hydrotheca- rather distant, small, 

 cup-shaped, and platted near the middle of the interuodes; supracalycine nematophores rather 

 long; a mesial uematophore at the base of each hydrotheca, two on each intermediate internode, 

 one on the proximal internode of the hydrocladium, one or two in the axil of each hydrocladium, 

 and two cauliue uematophores on eacli internode of the stem. 



Gonosome. Gonangia elongate, oval, smooth, narrowed below into a short peduncle by 



1 Condensed translation of the original description rearranged to suit the plan adopted in this work. 



- Koi- the purpose of preserving and registering the types of uew species the author has adopted the plan of 

 mounting three series of slides from the same type specimen, eaeh slide showing, so far as possible, the specific 

 character of the new species. These series were then distributed to the United States National Museum, the 

 Museum of the State University of Iowa, and the private collection of the author. 



