vol. 2, pt. 2.] A TAXONOMIC STUDY OF THE SALPIDAE METCALP. 179 



Sigl, 1912, b. Die Thaliceen u. Pyrosomen des Mittelmeers u. der Adria., etc., in 



Denkschriften der k. Akad. der Wissenschaften. vol. 88. 

 Streiff, 1908. Uber die Muskulatur der Salpen und ihre systematische Bedeutung. 



Zool. Jahrb., vol. 27, no. 1. 

 Tilesius, 1802. Abbildung und Beschreibung eines sonderbaren Seebeutels oder einer 



neuen Thetys-Species au3 dem Atlant. Ocean, Thetys vagina. Jahrbuch der 



Naturgescbichte, vol. 1. 

 Todaro, 1883. Sopra una nuova forma di Salpa (S. dolicosoma) . Atti Accad. Lincei 



(3), vol. 8. Roma. 

 Traustedt, 1885. Spolia Atlantica. Bidrag til Kundskab om Salperna. Danske 



Vid. Selsk. Skrift. (6), vol. 2 (1886). 

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This manuscript was completed for the United States Bureau of 

 Fisheries on July 10, 1915, and received for publication by the United 

 States National Museum on February 21, 1917. 



EXPLANATION OF TEXT FIGURES AND PLATES. 



Interpretation of index letters, numbers, and signs. These are the same in text 

 figures and plates. 



O The ball is dorsal, the pointed end of the rod is ventral. 



O 



~* The arrow points anteriorly. 



-> The previous two signs combined. 



4 



The endostyle in the text figures is generally shown in solid black, the peripharyn- 

 geal band as a dashed line. 



a=lateral portion of the dorsal eye in Salpa cylindrica. 

 on.=anus. 

 a. o.=atrial opening. 

 a. r.=atrial retractor. 



a. s.=atrial sphincter. The atrial sphincters are often numbered a. s. 1; 

 a. s. 2, etc. 



a. -y.=antero-ventral prolongation of ganglion. 



6=small-celled outgrowth from the ganglion. 

 6 / =large-celled outgrowth from the ganglion. 



b. e.=blood corpuscle. 

 b. s.=blood sinus. 



c.=caecum. 



c / .=caecum of right side, 

 (/'^caecum of left side. 

 c./.=ciliated funnel, dorsal tubercle. 

 cL=cloaca. 

 cl. ep.=cloacal epithelium. . 



cl. s.=cloacal siphon. 



<2.=duct of neural gland. 

 d. Z.=dorsal lamina. 

 d. m. l.= dorsal mid line. 



d. o.=aperture of duct of neural gland into the pharyngeo-atrial chamber. 

 dor. =dorsal. 

 e .= e ye, usually meaning the dorsal eye. 



