Iviii THE VOYAGE OF H.M.S. CHALLENGER. 



Order MONAXONIDA (p. !).» 



Suborder I. HALICHONDEINA (p. 1). 



Family I. H o M o R R H A p h i D ^ (p. 1). 



Subfamily 1. Eenierin^ (p. 1). 



Genera — 

 Halichondria (p. 1). | Petrosia (p. 9). 



Reniera (p. 14). 



Subfamily 2. Chalinin.e (p. 18). 



Genera — 

 Pachychalina (p. 19). | Chalma (p. 25). 



Siplionochalina (p. 29). 



Family II. Heterorrh aph ID^ (p. 31). 

 Subfamily 1. Phlceodictyin^ (p. 31). 



Genera — 

 Rhizochalina (p. 32). | Oceanapia (p. 36). 



Subfamily 2. Gelliin^ (p. 37). 



Genera — 

 Gellius (p. 37). I Gelliodes (p. 47). • 



Toxochalina (p. 49). 



Subfamily 3. Tedaniin^ (p. 50). 



Genera — 

 Tedania (p. 50). | Trachytedania (p. 57). 



Subfamily 4. Desmacellin^ (p. 58). 

 Genus Desmacella (p. 58). 



Subfamily 5. Hamacanthin.e (p. 59). 

 Genus Vomerula (p. 59). 



1 The pages referred to are those on which the diagnoses will be found. 



