of the Fishery Board for Scotland. 



207 



pelagic fish ova cannot be shown in the Table, but is clearly indicated in 

 the chart showing the comparative frequency of fish ova during the 

 various months and years for all the stations. Pelagic fish ova were 

 found in the bottom tow-net in 1889 at Station IV. in June ; in 1890 at 

 Station IV. in April and May, and at Station V. in May ; in 1891 at 

 Station I. iQ Ma)', and in the same month at Station IV. ; in 1892 at 

 Station VIII. in May ; and in 1894 at Station III. in Ai^ril. In the 

 records for all the seven years pelagic fish ova are three times described as 

 abundant, and this only in 1894, when they are so described once for 

 each of the three outer stations. 



(7.) EXPLANATION OF THE CHARTS (Plates IV. to VII.). 



Before concluding this paper on the tow-net gatherings collected in the 

 Firth of Forth in connection with the trawling investigations of the 

 Fishery steamer Garland during the years 1889 to 1895, and pub- 

 lished in the Annual Reports for these years, I desire to say a few w^ords 

 about the charts appended hereto, by way of explaining their contents. 

 These charts are intended to supplement what has already been said con- 

 cerning the distribution of a few of the organisms that are numerically or 

 otherwise of greater importance than the others in their relation to 

 fishery questions. The charts exhibit certain important features respect- 

 ing the distribution of these organisms that could not be readily shown 

 in the Tables, by indicating concisely and graphically the relative scarcity 

 or abundance of these organisms as well as their distribution vertically 

 and horizontally. The years and months are arranged in regular 

 sequence along the top of each chart. Where the organisms are present 

 in the tow-net gatherings they are indicated under four degrees of 

 frequency, viz. (1) as abundant, represented by the contraction " ab." ; 

 (2) as common, represented by " com. (3) as frequent, represented by 

 " fr."; and (4) as few or rare, represented by " f . or r." ; if the organisms 

 are altogether absent or are not referred to in the tow-net lists, this fact 

 is indicated by the word " none," which is the last in the series. These 

 abbreviations are used for each of the six stations, and are arranged along- 

 side of them. The tow-net records for each month are represented by 

 round dots; the dots are arranged to show whether the species referred to 

 on the chart was abundant, common, frequent, few or rare, or absent in 

 the gathering represented. Moreover, these dots are joined together by 

 thick or thin lines : the thick lines show that the records are for bottom 

 tow-net gatherings, and the thin lines for surface tow-net gatherings. 

 When the distribution of two organisms or groups of organisms are repre- 

 sented separately on the same chart, they are distinguished from each other 

 by using black and red lines. There is one other point in connection 

 with the charts that requires to be explained. It has been stated that, 

 for various reasons, the selected stations were not examined every month 

 during the seven years, and that there are now and again omissions of the 

 monthly records of tow-net fauna, either because no trawling was done, 

 or if done that the usual lists of the contents of the tow-nets could not be 

 prepared. The months when such omissions occurred are indicated on the 

 charts by the thick and thin lines when crossing the column or columns 

 under these months being discontinuous. 



The first chart (Plate IV.) illustrates the distribution of Calanus 

 finmarchicus and Temora longicornis. The first is shown by the black 

 lines, the other by the red lines. 



The second chart (Plate V.). illustrates the distribution of Sagitta 

 hipundata and the Coelenterata. Sagitta is represented by the black 

 lines, and the Coelenterata by the red lines, 

 o 



