REPORT ON THE SIPHONOPHOR^E. 119 



The genus Aglaisma (PI. XL.) comprises those monogastric Eudoxidse which arise 

 from the polygastric Diphyid genus Calpe (Genus 31, PI. XXXIX.). Its bract is nearly 

 cuboidal, similar to that of Cuboides (Genus 13), but differing from it in the possession of 

 a pyramidal, trigonal, or pentagonal apophysis, which descends vertically from the dorsal 

 and basal part of the cube. It is further distinguished by the possession of four radial 

 canals, arising from the small subcentral phyllocyst. Two of these four cruciate canals 

 are slender and vertical (an ascending and a descending), two others sacculate and hori- 

 zontal (a right and a left). 



The genus Aglaisma was founded in 1829 by Eschscholtz for a Tropical Atlantic 

 species of monogastric Diphyidse, which he called Aglaisma baeri (1, p. 129) ; it is 

 possibly identical with our Aglaisma gegenbauri. Afterwards Huxley, 1 in 1859, gave 

 an accurate description of two nearly related species, which he called Aglaismoides 

 eschscholtzii and Aglaismoides elongata. He suspected rightly that the former might 

 be the Eudoxia of the common Mediterranean Abyla pentagona. The other species, 

 Aglaismoides elongata, might be the Eudoxia of Calpe huxleyi. During my stay in 

 the Canary Islands (1867) I observed the development of the species described in the 

 following pages, from Calpe gegenbavri. It occurs also in a bottle of the Challenger 

 collection, taken at Station 346. 



Aglaisma gegenbauri, n. sp. (PI. XL.). 



Habitat. — Tropical and Subtropical Atlantic, Station 346 ; April 6, 1876 ; lat. 

 2° 42' S., long. 14° 41' W. Surface. 



Canary Islands, Lanzerote, February 1867 (Haeckel). 



Bract (fig. 13, b, lateral view from the right side ; fig. 14, b, from the left side ; fig. 

 15, basal view ; fig. 16, apical view ; fig. 17, dorsal view ; fig. 18, ventral view). — The 

 hydrophyllium or bract is subregularly cuboidal in its apical or superior half, in its basal 

 or inferior obliquely pyramidal, bevelled off at the ventral and basal face. The length 

 or height of the bract is 1*2 to 1*5 mm., the breadth 0"6 to - 8 mm. 



The apical or superior face of the bract (figs. 13-16, ua) is nearly square, slightly 

 concave, with four equal concave edges. The phyllocyst and its two lateral caeca shine 

 through it in the apical view. The ventral or anterior face (fig. 18, uv) has the same 

 square form, but is somewhat longer, and dilated towards the concave basal edge. The 

 dorsal or posterior face of the bract (fig. 17, ud) is more concave, and has the form of a 

 bilateral pentagon, which is twice as long as broad. Its odd superior edge is horizontal, 

 and half as long as the two divergent superior lateral edges. These are somewhat longer 

 than the two convergent inferior lateral edges, which meet in the basal apex of the 



1 9, p. 60, pi. iv. figs. 2, 3. 



