io THE TURBELLARIA 



rhynchus, v. Gr., M. ; Acrorhynchus,. v. Gr.; Macrorhynchus, v. Gr., M. ; 

 Gyrator, Ehrb. ( = Prostomum, Oerst.), two genital pores, the female being 

 anterior to the male ; G. linearis, Oerst., F. ; Hyporhynchus, v. Gr., M. ; 

 Schizorhynchus, Hallez (30). FAMILY 6. VORTICIDAE, v. Gr., mono- 

 gonoporous ; mouth usually near the anterior end ; accessory female 

 copulatory organ present; pharynx barrel-shaped. SUB-FAMILY 1. 

 EUVORTICINAE, v. Gr., with brain and pharynx well developed ; germarium 

 small ; free living. SchuUzia, v. Gr. ; Provortex, v. Gr. ; Vortex, Ehrb. ; 

 V. viridis, with chlorophyll, F. ; Opistoma, O. Schm. (see 59) ; Jensenia, 

 v. Gr. ; Derostoma, Oerst., vitellarium reticulate. SUB - FAMILY 2. 

 PARASITICA, v. Gr., pharynx and brain feebly developed ; germarium 

 large. Graffilla, v. Jher. (see 4), Fig. III. 1 ; and Anoplodium, 

 Schneider ; occur parasitic in Gastropoda, and the latter genus in 

 Holothurians ; Syndemii*, Silliman, parasitic in Echinids, is stated to 

 contain haemoglobin in its parenchyma ; Fecampia, Giard (20), parasitic 

 in decapod Crustacea, which it leaves when mature. FAMILY 7. 

 SOLEXOPHARYNGIDAE, v. Gr. Monogonoporous ; single germarium ; 

 mouth posterior ; pharynx long and tubular ; Solenopharynx, v. Gr. 



SUB-ORDER 2. ALLOIOCOELA, v. Gr. Rhabdocoelida, in which the 

 intestine may have irregular caeca ; testes numerous (follicular) ; no 

 conspicuous chitinous copulatory organ. (For an account of this sub- 

 order see 5 and 59.) 



FAMILY 1. PLAGIOSTOMIDAE. Without an otolith ; usually a single 

 genital pore ; pharynx variabilis. SUB-FAMILY 1. PLAGIOSTOMIXAE, v. Gr. 

 Mouth anterior ; pharynx directed forwards ; genital pore posterior ; 

 germaria and vitellaria. Plagiostoma, 0. Schm. ; Vorticeros, 0. Schm. 

 (Fig. III. 7). SUB-FAMILY 2. ALLOSTOMIXAE, Bohrn. Pharynx directed back- 

 wards ; mouth posterior. Allostoma, P. J. van Ben (Fig. III. 9) ; Entero- 

 stoma, Clap. SUB-FAMILY 3. CYLIXDROSTOMIXAE, v. Gr. A ciliated circular 

 groove; a common enteric and genital pore; a germ-vitellarium. Cylindro- 

 stoma, Oerst. (Fig. III. 8); Monoophorum, Bohmig. SUB-FAMILY 4. 

 ACMOSTOMINAE, v. Gr. Genital pore posterior. Acmostoma ; commensal 

 in Cyprina islandica. FAMILY 2. MONOTIDAE. With a single otolith ; 

 pharynx plicatus directed backwards ; paired germaria and vitellaria ; 

 digonoporous, M. Monotus, Dies. ; M. hirudo is parasitic ; Automolos, 

 v. Gr. FAMILY 3. BOTHRIOPLANIDAE, Vejd. Mouth post-central ; mono- 

 gonoporous ; pair of ciliated pits, F. Bothrioplana, Vejd. (59). 



SUB-ORDER 3. ACOELA, Uljanin. Rhabdocoelida, in which the cavity 

 of the enteron is obliterated by the concrescence of its walls ; the mouth 

 leads through a simple pharynx directly into the digestive syncytiuni ; 

 otocyst present ; a pair of ovaries (see 6, 24, and 50). 



FAMILY 1. PROPORIDAE. Monogonoporous. Proporus, v. Gr. ( = 

 Schizoprora, Schm.); HaploJiscus, Weldon (62, for recent account see 52) ; 

 Monoporus, v. Gr. ( = Proporus, Schm.) FAMILY 2. APHAXOSTOMIDAE, 

 with female pore separate from and in front of male pore, with sperma- 

 theca. Aphanostoma, Oerst. ; Convoluta, Oerst. ; Amphichoerus, v. Gr. ; 

 PolychoeniSi Mark. 



