for the Microscope. 83 



opposite each other, in pairs. Small and parasitic on 

 different species of sea-wrack. 



642. SEA-FIR CORALLINE (Sertularia abietind), Erect 

 and rigid, from four to ten inches high. Regularly pinnate 

 and flattened. Cells nearly opposite, rather small, swollen 

 at the base so as to resemble a miniature Florence flask. 

 (PI. VIIL, fig. 14.) 



643. SEA-HAIR CORALLINE (Sertularia operculata). 

 From four inches in height, growing in tufts; branches 

 very slender, hair-like, and graceful ; cells opposite, with 

 the outer angle ending in a point. Common on large 

 seaweeds. (PL VIIL, fig. 19.) 



644. SHEEP'S-TAIL CORALLINE (Sertularia argented). 

 From six inches in height, with compound forked branches. 

 Cells nearly opposite, like a Florence flask with a bent 

 neck. On oyster-shells and seaweeds. (PL VIIL, fig. 17.) 



645. SEA-CYPRESS CORALLINE (Sertularia cupressina). 

 Larger than the last, and also with compound forked 

 branches. Cells nearly opposite, with the margin cut 

 into two or three teeth. Not uncommon on mussels and 

 oysters. 



646. LOBSTER-HORN CORALLINE (Antennularia anten- 

 nina). Eight inches in height. Grows in clusters of 

 unbranched stems, which are surrounded at regular dis- 

 tances by whorls of delicate branchlets. Cells small, bell- 

 shaped. 



647. BRANCHED-HORN CORALLINE (Antennularia ra- 

 mosa}. Resembling the last; but with the main stem 

 branched, and the hair-like branchlets are longer. On 

 .old shells and stones in deep water. 



648. SICKLE CORALLINE (Plumularia falcatd). From 

 six to twelve inches in length, rising in spiral turns, with 

 branches on the outer side. The branches are pinnate. 

 Cells on the branches and branchlets in two rows pointing 

 alternately to opposite sides. (PL VIIL, fig. 15.) 



649. SEA BRISTLES (Plumularia setacea). Scarcely 

 reaching six inches in height, pinnate. Cells very remote, 

 bell-shaped, with an even margin. Parasitical on other 

 zoophytes. (PL VIIL, fig. 18.) 



62 



