484 C. A. NILSSON-CANTELL 



Genus Lepas. 



L. pectinata Spengler, 1793. 



Syn. Nilsson-Cantell, 1921. 



Discussion: All the specimens are very typical. To the description of 

 the species nothing need be added here. The species is in the collection as- 

 sociated with L. australis. Some remarks of biological interest may yet be 

 noted. The individuals, situated on stalks o{ Macrocystis, grow closely -together, 

 a feature which Broch (1922) has demonstrated by studying individuals from 

 OS sepium and Janthina. The material contains individuals of different stages. 

 No pupa stages seem to be represented. On the plates of the capitulum younger 

 specimens of L. australis were placed, also pupa stages, which belong to L. 

 australis, of which I have studied individuals numbered 595, consisting of many 

 individuals of all sizes. Under the same number 595 only three fullgrown 

 specimens of L. pectinata were taken. I can here state that L. australis can 

 grow on Macrocystis and on the plates of L. australis and pectinata. I never 

 found in this collection specimens of L. pectinata situated on each other or on 

 L. australis. This may perhaps be another question of biological interest not 

 mentioned by Broch, who has raised other problems as regards the fixation 

 not possible to explain on spirit material. In some smaller individuals pec- 

 tination was observed on the valves but not in the fullgrown. These smaller 

 do not, however, belong to some of the two varieties known. 



Localities: Masatierra. On Macrocystis drifted from the continent, 28. 

 iv. 1917. No. 594 and 596, many specimens, associated with L. australis ivelt- 

 neri. No. 595, a few specimens, also together with L. australis weltnen. — 

 Cumberland Bay, on a buoy, 3. i. 1917, No. 205. One specimen. 



These localities are not quite new as according to Weltner (1897) L. 

 pectinata was found by Dr. Plate on floating algae between the Juan Fernan- 

 dez Islands and Valparaiso. 



Distribution: Cosmopolitan, mostly in tropical seas. Pelagic on floating 

 objects. 



L. anatifera Linne, 1767. F'ig. i. 

 Syn. Nilsson-Cantell, 1921. 



Discussion and complementary description: Many fullgrown individuals of 

 this species were collected. It is of interest to note that this species is very 

 variable, as also stated by several authors. This caused me (1928) for instance 

 to describe L. testudinata AURIVILLIUS (1892) as a variety of L. anatifera z.nA 

 a new variety nonfurcata (Nilsson-Cantell, 1927). 



In Dr. Backstrom's material I have found two forms of the species 

 slightly different in shape. It is, however, not possible to describe a new 

 variety, as the differences are neither very great nor constant. Both types are 

 figured here (fig. i). 



