of the Fishery Board for Scotland. 189 
The only points of interest in connection with the distribution of 
Pseudocalanus elongatus, so far as can be made out from the tow-net 
records of its occurrence, seem to be these-—(1st) if an average of all the 
records of this Copepod for the seven years be taken, the numbers for 
April and May will be seen to be greater than those for all the other 
months added together ; and (2nd) that the maxima of the records for 
the seven years occur in 1891, 1892, and 1893. 
Anomalocera patersont, which from its very large size and beautiful 
colour is easily detected among the tow-net gatherings, is recorded a con- 
siderable number of times during the seven years. The greatest total 
number of records for any of the years is that for 1891, the number for 
that year being nearly double that for any other of the whole seven, as 
shown by the formula. 
Formula (1) shows the number of records of Anomalocera for each 
of the seven years :— 
Numbers of the Years, - - 1889. 1890: 189%. 1892. 1893. 1894. 1895. 
Total number of Records for each Year, 7 13 17 6 9 4 6 
This formula shows a gradual increase to the maximum, then a some- 
what irregular decrease. 
Formula (2) shows the total number of records of Anomalocera for 
each of the twelve months :— 
Names of the Months, Jan. Feb. Mar. April. May. June. July. Aug. Sept. Oct. Nov. Dec. 
Number of Records for 
Sr Moh \o Oosawa bot fee yin HRM g 
It will be observed that by tar the largest number of records for this 
species occur in May and June; they are much fewer in July, August, 
and October, and rarely, or none at all, in the other months. It would 
appear from this that Anoma/locera is not resident in the estuary, but is 
only a summer visitor, and, as Formula (1) shows, its visits are fairly 
regular. 
Formula (3) shows the total number of records of Anomalocera for 
each of the six stations :— 
Inner Stations. Outer Stations. 
Numbers of the Stations, = - ie L. JUL IV. Vi Vee IX. 
Number of Records for each Station - 5 5 1 15 16 19 
The difference between the inner and the outer stations is very marked 
here, but is only what might be looked for if Anomalocera be only a 
“visitor” to the estuary and its vicinity. This also explains why 
Station IV. appears to have been so rarely visited, for, being a migrant, 
Anomalocera is more likely to keep as much as possible to the open 
water, and avoid inshore localities. 
The distribution of the other species mentioned in the lists of tow-net 
fauna does not call for special analysis ; but a few of them are of interest 
because of their beauty, their rarity, or because of their structural 
differences aud habits. 
Metridia hibernica, which is of an elongate form, and has a long and 
moderately slender abdomen, is recorded only once during the seven 
_years—viz., at Station IX. in May 1892, when a few specimens were 
obtained. Metridia is a comparatively large Copepod. 
Candace pectinata is also moderately large, and is readily noticed by 
its dark chocolate-coloured swimming feet. There are several records of 
this species in the lists of tow-net invertebrates. 
Parapontella brevicornis appears to be only once recorded for the seven 
years, but the species is not very rare locally. 
