LINDSAY, ON THE PROTOPHYTA OF NEW ZEALAND. 103 
species, varying considerably in size and in relative length 
and breadth. Sometimes the sides are conspicuously un- 
equal; . . . . but generally the inequality is small and 
often scarcely, if at all, perceptible ; so that valves might 
pass for a Navicula were it not for an indescribable -facies 
which to the initiated eye proclaims its true position, The 
apices are neither capitate nor produced; but a slight con- 
traction just beneath them produces a very characteristic 
effect. As is common among species both of Cyméella and 
Cocconema, the frustules vary much in length and breadth. In 
length they range from -0025” to 0035”, and in breadth the 
shortest specimens are often equal to the longest: the average 
being about 0007.” The striz are about 19 in. :001”.” 
C. apiculata, which was included in my list of Otago Dia- 
tomacez published in the ‘ Linnean Society’s Journal,’ was 
an error subsequently rectified by Dr. Greville.* The diatom 
in question was really Cymatopleura apiculata, belonging to 
the family Surirellee. 
Genus 24. Cocconema. 
62. lanceolatum, Ehrb. 
Occurs also in North America; previously found in New 
Zealand (Smith). 
Genus 25. Amphora. 
63. ovalis, Kutz. 
», 86. Gomphonema. 
64. constrictum, Ehrb. 
65. curvatum, Kutz. 
66. cristatum, Ralfs. 
67. Augur, Ehrb. 
Occurs in Europe, Asia, Africa, America, and Australia, 
but not British (Pritchard). Throughout Europe (Raben- 
horst 
D. Greville remarks,+ “‘ May or may not be British. If 
it be considered a variety of G. cristatum, it is British. Smith 
is doubtful. I have considered it as distinct and not British.” 
68. tenellum, Kiitz. 
69. intricatum, Kitz. 
70. Vibrio, Ehrb. 
71. dichotomum, Kiitz. 
72. equale, Greg. 
* Letter, March 5th, 1866. 
+ Letter, February 17th, 1866. 
