vol. 2, pt. 2.] A TAXONOMIC STUDY OF THE SALPIDAE METCALF. 175 



)3, 2 Appendages in solitary form less than half as long as the body, 

 body muscles forming complete uninterrupted loops: 

 body muscles in aggregated zooid with from 3-5 fibers 



each (type) democratica. 



b, 5 Body muscles in both solitary and aggregated forms 4, confined to the 

 dorsal half of the body, forming an anterior and a posterior X-shaped 



group Pegea. 



/3, 1 Aggregated zooid with a pair of posterolateral appendages, 

 usually of unequal length, eye somewhat stalked. 



confederate, subspecies bicaudata 

 /3, 2 Without the characteristics specified under j3, 1 confederata. 



b, 6 Solitary form with numerous tubular appendages from different parts of 



the body Traustedtia. 



bb, 1 Appendages in solitary form 20 or more, gut forming a horizontal 

 spindle-shaped mass: aggregated zooid probably not known. 



radiata. 



bb, 2 Appendages in solitary form not more than 13, gut forming a 



vertical spindle-shaped mass. Aggregated form with a single 



unequal pair of postero-lateral appendages. 



13, 1 Appendages of the solitary form 8, the posterior pair about 



as long as the body. Oral muscles continuous across the 



mid-dorsal line (type) multitentaculata. 



0, 2 Appendages of the solitary form 13. Oral muscles very 

 short dorsally, hardly extending above the angles of the 



mouth multitentaculata, subspecies bicristata. 



C. Gut in both solitary and aggregated forms making a compact "nucleus," in which 

 the course of the intestine can not be clearly seen without dissection. 

 Sphaerodaea. 



c, 1 Body muscles in solitary form widely interrupted ventrally: aggregated 



zooids asymmetrically more or less pointed in front and behind, body 



muscles not very asymmetrical Salpa. 



cc, 1 Body muscles in solitary form all about parallel. Gut nucleus in 

 aggregated zooid on mid-line, pushing the posterior protuber- 

 ance to one side; body muscles IV and V not in contact 

 laterally. 

 k, 1 Anterior and posterior appendages in aggregated zooid 

 about \ as long as body, no swollen spinose areas at 



base of atrial siphon maxima. 



k, 2 Anterior and posterior appendages in aggregated zooid 



about $ as long as body, 2 unequal spinose thickenings 



of the test dorsally near the base of the atrial siphon. 



maxima, variety tuberculata . 



cc, 2. Body muscles I to III in the solitary form in contact dorsally, the 



rest parallel; body muscles IV and V in the aggregated zooid in 



contact laterally. 



k, 1. Neither solitary nor aggregated forms bearing spinose 



ridges (type) fusiformis. 



k, 2. Both solitary and aggregated forms bearing spinose ridges. 



fusiformis, form aspera. 



cc, 3. Body muscles I to IV in the solitary form in contact dorsally. In 



aggregated zooid body muscles I to III and IV and V are fused 



dorsally to form 2 broad bands. These 2 bands are in contact 



dorsally and may be united cyclindrica. 



2621— Bull. 100, vol. 2—19 12 



