136 COELENTERATA. 



cartilaginous strip of endoderm beneath each of the 8 or 12 peroniums, close 

 to which are the tentaculocysts. 



Sub-fam. 1. Liriopidae. 4 gonads and 4 radial canals ; 8 tentaculocysts 

 (4 primary perradial and 4 secondary iuterradial). Permanent tentacles, 

 4 or 8. Liriantha H. ; Lirwpe Lesson ; Glossoconus H. ; Glossocodon H. 



Sub-farn. 2. Carmarinidae. 6 gonads in the course of the 6 radial canals, 

 12 tentaculocysts (6 primary interradial, and 6 primary perradial). Tentacles 

 6 or 12. Geryones H. ; Geryonia, Per. and Les., without centripetal canals ; 

 Carmaris H.; Carmarina H. (Fig. 101), with centripetal canals. 



Order 6. "^ARCOMEDUSAE.* 



Craspedota with free auditory tentacles. Tentacles inserted dorsally 

 on the ex-umbrella, and connected ivith its edge by peroniums. Radial 

 canals when present in the form of flat radial gastric pouches. 



So far as is known the Narcomedusae are without the hydroid 

 phase. There is a thickened ectodermal ring at the umbrella edge 

 which is prolonged on to the ex-umbrella to the insertion of the 

 tentacles as the peroniums (Fig. 96). The peripheral part of the 

 umbrella is lobed. The gonads are primitively in the ventral or 

 lateral wall of the stomach, whence they are often spread out on 

 the radial gastral pouches. The circular canal is either obliterated, 

 or else in festoons (Fig. 96), following the edge of the lobes to 

 open into the gastral pouches. The radial structures (tentacles, 

 lobes, and pouches) vary in number they may be rarely 4, usually 

 8 or more to 32. Otoporpae or peronial streaks of ectoderm passing 

 from the auditory tentacles may be present (Fig. 96). 



Fam. 1. Cunanthidae. With wide, pouch-like radial canals, which are 

 connected with the circular canal by double peronial canals (festoon canals, 

 Fig. 96). With otoporpae. Ounantha H. ; Cunarcha H. ; Cunoctantha H. ; 

 Cunina Esch. ; Cunissa H. 



Fam. 2. Peganthidae. Without radial canals and gastral pouches, but 

 with a festoon canal, with otoporpae. Polycolpa H. ; Polyxcnia Esch. ; Pegasia 

 Per. and Les. ; Pegantha H. 



Fam. 3. Aeginidae. With a circular canal which communicates with the 

 stomach by double peronial canals ; with internemalf gastral pouches ; without 

 otoporpae. Aegina Esch. ; Aeginella H. ; Aegineta Gegenbaur ; Aeginopsis 

 Brandt; Aeginura H. ; Aeginodiscus H. ; Aeginodorus H. ; Aeginorhodtisld. 



Fam. 4. Solmaridae. Without circular canal and peronial canals ; sometimes 

 without radial canals, sometimes with modified radial canals (pernemal or inter - 



* E. Haeckel, Monographic d. Medusen. Jena, 1879. 



t Internemal gastral pouches are really interradial pouches projecting from 

 a radial (pernemal) pouch (suppressed in the Acginidae] into the lobes of the 

 peripheral part of the umbrella. Each original radial pouch gives off two of 

 these internemal pouches, one into one lobe and the other into the adjacent 

 lobe. The two internemal pouches of one radial gastric pouch are therefore 

 separated by the double peronial canal, or festoon-like loop of the circular 

 canal, which runs into the central stomach radially. 



