On looking at the total inflorescence of the _Nardus_ we see that we have a number of spikelets seated on the sides of an axis: this is then a spike of spikelets, or, shortly, a _Spike_[9] (Fig. 5). _Mibora_ and _Lepturus_ afford other examples. In _Panicum_, _Cynodon_ (Fig. 2) and _Spartina_ we have groups of such spikes. The _Poa_ inflorescence is, however, different. It consists of a loose branched system of spikelets. Botanists term such a loosely branching system, where each branch ends in a flower, a _panicle_: here then we have a panicle of spikelets, or, shortly, a _Panicle_. _Aira_, _Agrostis_, _Calamagrostis_, _Avena_, _Catabrosa_ (Fig. 4) and many others afford further examples. In _Dactylis_ we have a condition of affairs between the two extremes given: the inflorescence is not so close a spike as _Nardus_, and not so open a panicle as _Poa_--it is rather a spike-like panicle, partaking of the nature of both. A special type of this (Foxtail) occurring in certain grasses--e.g. _Phleum_, _Alopecurus_, _Phalaris_ and _Lagurus_,--is so characteristic as to be worth noting (Fig. 3). There is also another aspect of these inflorescences which is not without interest as showing how diagnostic characters may be obtained from purely external features, easily observed in the field. We have seen that in _Nardus_ the spikelets are arranged on one side only of the rachis, or main axis, so that about three quarters of the circumference of the latter is bare; whereas in _Lolium_--with which _Agropyrum_ and _Brachypodium_ agree in this respect--the spikelets are on opposite sides, leaving the intervening two quarters, i.e. half its surface, of the circumference of the axis naked. In _Cynosurus_ and the simpler forms of _Dactylis_, we find the spikelets crowded round about three quarters of the surface of the rachis, leaving the fourth quarter naked; and, finally, in _Phleum_, _Alopecurus_, _Hordeum_, and _Anthoxanthum_ the spikelets cover the entire surface. In the first (_Nardus_) and third examples (_Cynosurus_, _Dactylis_) where the spikelets are turned to one side, the inflorescence is said to be _secund_.